Answer:
Bulbs in series will be dim
Explanation:
The voltage remain constant in a series circuit, thus bulbs in series circuit will get equally distributed voltage which is not equal to the voltage across the circuit or the voltage supplied
In case of parallel circuit, the voltage across the bulb is the same as the voltage across the circuit due to which bulbs will be brighter in case of parallel circuit
When point charges q1 = +1.2 μC and q2 = +4.1 μC are brought near each other, each experiences a repulsive force of magnitude 0.67 N. Determine the distance between the charges.?
Answer:
2.57 cm or 2.57×10⁻² m
Explanation:
From coulomb's law,
F = kqq'/r²................. Equation 1
Where F = force between the charges, q and q' = The first and second charge respectively, k = constant of proportionality, r = distance between the charges.
Making r the subject of equation 1
r = √(kqq'/F)................ Equation 2
Given: F = 0.67 N, q = 1.2 μC = 1.2×10⁻⁶ C, q' = 4.1×10⁻⁶ C
Constant: k = 9×10⁹ Nm²/C².
Substitute into equation 2
r = √( 1.2×10⁻⁶×4.1×10⁻⁶×9×10⁹/0.67)
r = √(66.09×10⁻³)
r = √(6.609×10⁻⁴)
r = 2.57×10⁻² m
r = 2.57 cm or 2.57×10⁻² m
Hence the distance between the charge = 2.57 cm or 2.57×10⁻² m
Which of the following describes how net work is determined?
A. The difference in the initial and final forces applied
B. The net force on an object applied for a brief second
C. The initial force applied to an object over a distance
D. The net force on an object applied over a distance
Answer:
D. The net force on an object applied over a distance
Explanation:
Work can be defined as the product of force multiplied by a distance
Where
F = force [Newtons]
d = distance = [meters]
Therefore:
Work = F * d
Work in units of Joules [J]
Process in which permanent deformation of metals occurs due to applied stress and results in breaking of bonds and then reforming of bonds with new neighbors. After removing of the stress, the metal does not return to its initial form.
Answer:
This process involves the motion of dislocations and is termed slip (or glide in some textbooks)
Explanation:
Plastic deformation of metals (and other crystalline materials) usually occurs by slip, which is the sliding of planes of atoms over one another by dislocation movements.
On a microscopic scale, stress causes planes of crystalline objects to leave their original position and slide over other planes into new positions, these microscopic movements manifest as a slip on a macroscopic scale. And the planes do not return back to their original position after the removal of the dislocation-causing stress.
"Compared to infrared radiation, does ultraviolet radiation have longer or shorter wavelengths? Does ultraviolet radiation have higher or lower energy per photon?"
Answer:Ultraviolet radiation has shorter wavelengths and higher energy than infrared radiation.
Explanation: Electromagnetic radiation radiations which have both electrical and magnetic properties,they can be transmitted through space or through a medium.
It includes Gamma radiation, infra-red, visible light, Ultraviolet radiation etc they occur with different wavelength, the lower the wavelength the higher the Energy dissipated per photon. According to their order of decreasing wavelength and increased energy they are classified as follows.
RADIO WAVE, MICRO WAVE, INFRA-RED, VISIBLE LIGHT, ULTRAVIOLET RAY, X-RAY, GAMMA RAYS.
Ultraviolet radiation has shorter wavelengths and higher energy per photon compared to infrared radiation.
Explanation:Ultraviolet radiation has shorter wavelengths compared to infrared radiation. While infrared radiation has wavelengths between 700 nm and 1 mm, ultraviolet radiation has wavelengths between 100 nm and 400 nm.
Ultraviolet radiation also has higher energy per photon compared to infrared radiation. This is because energy is inversely proportional to wavelength, so shorter wavelengths have higher energy.
For example, ultraviolet radiation is responsible for causing sunburns and skin damage, which is evidence of its higher energy compared to infrared radiation.
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A 150 g baseball pitched at a speed of 45 m/s is hit straight back to the pitcher at a speed of 60 m/s. What is the magnitude of the average force on the ball from the bat if the bat is in contact with the ball for 9.5 ms?
Answer:
The average force is 1578.94 N.
Explanation:
Given that,
Mass of baseball = 150 g
Speed = 45 m/s
Speed of pitcher = 60 m/s
Time = 9.5 ms
We need to calculate the average force
Using formula of impulse
[tex]J=\Delta p[/tex]
[tex]J=m\Delta v[/tex]...(I)
[tex]J=F\Delta t[/tex]....(II)
From equation (I) and (II)
[tex]F=\dfrac{m(v_{f}-v_{i})}{\Delta t}[/tex]
Where, m = mass of baseball
[tex]v_{f}[/tex] = final velocity
[tex]v_{i}[/tex] = Initial velocity
[tex]\Delta t[/tex] = time
Put the value into the formula
[tex]F=\dfrac{150\times10^{-3}\times(60-(-40))}{9.5\times10^{-3}}[/tex]
[tex]F=1578.94\ N[/tex]
Hence, The average force is 1578.94 N.
Answer:
F = 1657.89 N
Explanation:
given,
mass of the baseball, m = 150 g
initial speed, u = 45 m/s
final speed, v = 60 m/s
time of contact,t = 9.5 ms
we know,
impulse is equal to change in momentum
J = m (v - u)
J = 0.15 x (60-(-45))
J = 0.15 x 105
J = 15.75 Kg.m/s
We also know that impulse
J = F x Δ t
F x 9.5 x 10⁻³ = 15.75
F = 1657.89 N
The magnitude of the average force is equal to F = 1657.89 N
At what angle with the ground should a projectile be thrown to reach the maximum distance? a.) 0° with the ground b.) 45° with the ground c.) 62° with the ground d.) 82° with the ground
Answer:
B
Explanation:
With projectiles, the maximum range is always achieved at a 45 degree launch angle.
FM radio ________________. a. had a somewhat shorter range than AM radio, but better sound quality. b. was widely adopted in the 1950s, when radio started playing more music. c. had a scratchier sound that was okay for talk radio, but not for music. d. was able to carry signals farther than AM radio. e. was developed by Guglielmo Marconi.
Answer:
(A) FM Radio had a somewhat shorter ranger than AM radio, but better sound quality.
Explanation:
FM Radio was invented in 1933 by Edwin Armstrong who was an American engineer. FM stands for frequency modulation and AM stands for Amplitude Modulation.
FM is used for most broadcasts of music and FM radio stations use a very high-frequency range of radio frequencies.
In FM Radio, the sound is transmitted through changes in frequency. Both FM and AM radio signals experience frequent change in amplitude, they are far less noticeable on FM.
When switching between stations, FM antenna is alternating between different frequencies, and not amplitudes and this produces a much clearer sound and allows for smoother transitions with little to no audible static.
FM signals can be interfered by barriers and this could affect the signal strength. FM Radio signals are more clearer in a mountainous area that has no barrier.
AM radio was able to carry signals farther than AM radio.
the measure of each exterior angle of a regular pentagon is ___ the measure of each exterior angle of a regular nonagon
Answer:
(a) 72°
(b) 40°
Explanation:
PENTAGON
First, we calculate the total angles in a Pentagon using:
180(n - 2)
Where n = number of sides of the polygon, in this case, 5.
Hence, the total angle in a polygon is
180(5 - 2) = 180 * 3 = 540°
Therefore, each angle will be:
540°/5 = 108°
Because the interior angle and exterior angle form a straight line (180°), the exterior angle of a regular pentagon will be:
180 - 108 = 72°
The exterior angle of a regular Pentagon is 72°
NONAGON
First, we calculate the total angles in a Nonagon using:
180(n - 2)
Where n = number of sides of the polygon, in this case, 9.
Hence, the total angle in a polygon is
180(9 - 2) = 180 * 7 = 1260°
Therefore, each angle will be:
1260°/9 = 140°
Because the interior angle and exterior angle form a straight line (180°), the exterior angle of a regular nonagon will be:
180 - 140 = 40°
The exterior angle of a regular Nonagon is 40°
Final answer:
Each exterior angle of a regular pentagon, which measures 72 degrees, is greater than each exterior angle of a regular nonagon, which measures 40 degrees, because the sum of the exterior angles of any polygon is always 360 degrees.
Explanation:
The question asks how the measure of each exterior angle of a regular pentagon compares to the measure of each exterior angle of a regular nonagon. To answer this, first, we need to understand that the sum of the exterior angles of any polygon is always 360 degrees, no matter the number of sides. Therefore, to find the measure of each exterior angle of a polygon, we simply divide 360 degrees by the number of sides.
For a pentagon, which has five sides, each exterior angle has a measure of 360 ÷ 5 = 72 degrees. For a nonagon, which has nine sides, each exterior angle has a measure of 360 ÷ 9 = 40 degrees. Therefore, the measure of each exterior angle of a regular pentagon is greater than the measure of each exterior angle of a regular nonagon.
Four charges are the corners of a square with B and C on opposite corners. Charges A and D on the other two corners have equal charge while both B and C have a charge of +1.0 C. What is the charge on A so that the force B is zero?
Final answer:
The charge on A should be -2.0 C in order for the force on B to be zero.
Explanation:
In order for the force on charge B to be zero, the charge on A must be equal in magnitude but opposite in sign to the combined charge of charges C and D at the other corners of the square. Since both B and C have a charge of +1.0 C, A must have a charge of -2.0 C. This creates a symmetric distribution of charges, resulting in a net force of zero on charge B.
Henrietta is going off to her physics class, jogging down the sidewalk at a speed of 3.95 m/s . Her husband Bruce suddenly realizes that she left in such a hurry that she forgot her lunch of bagels, so he runs to the window of their apartment, which is a height 39.9 m above the street level and directly above the sidewalk, to throw them to her. Bruce throws them horizontally at a time 6.50 s after Henrietta has passed below the window, and she catches them on the run. You can ignore air resistance.
Part A. With what initial speed must Bruce throw the bagels so Henrietta can catch them just before they hit the ground?
Express your answer using three significant figures.
Part B. Where is Henrietta when she catches the bagels?
Express your answer using three significant figures.
Answer:
Part A 12.9 m/s
Part B 36.9 m
Explanation:
Henrietta ran at 3.95 m/s. She was 6.5 seconds away from from the window when Bruce throws the bagel. This equates to a distance of d
[tex]d= 3.95\times6.5=25.675[/tex] (distance = speed x time)
If Bruce throws the bagel horizontally, the vertical component of the motion is purely under gravity with initial speed of 0 m/s. Using one of the equations of motion for the vertical motion,
[tex]h=ut+0.5at^2[/tex]
h = 39.9 m (height of the building)
a = 9.8 (acceleration of gravity)
[tex]t=\sqrt{\dfrac{2\times39.9}{9.8}}= 2.85[/tex]
During this time, Henrietta will have travelled another distance e
[tex]e =3.95\times2.85=11.2575[/tex]Therefore, Henrietta would have jogged a total distance of 25.675 + 11.2575 m = 36.9325 m.
The horizontal speed with which Bruce must throw the bagel is the total distance travelled by Henrietta divided by the time it takes to land vertically i.e.
[tex]v=\dfrac{36.9325}{2.85}=12.96[/tex]
Therefore, the speed of throw is 13.0 m/s.
Henrietta was 36.9 m from the window when she caught the bagel.
Part A. The speed at which the bagel was thrown horizontally is 12.9 m/s.
Part B. The total distance traveled by Henrietta when she caught the bagel from the window is 36.9325 m.
How do you calculate the speed of the bagel?Given that, the speed of Henrietta is 3.95 m/s. When Bruce throws the bagel, the time difference between both of them is 6.5 seconds. Hence the distance can be calculated as given below.
Distance D = Speed [tex]\times [/tex] Time
[tex]D = 3.95 \times 6.50[/tex]
[tex]D = 25.675 \;\rm m[/tex]
Part A
Given that Bruce throws the bagel horizontally, then during the motion, the initial speed will be zero and the vertical component will have gravitational acceleration. In this case, the time required in motion can be calculated by the equation given below.
[tex]s = ut + \dfrac {1}{2} at^2[/tex]
Where, s is the distance, a is the acceleration, t is time and u is the initial speed.
For the horizontal motion, s = 39.9 m, g = 9.8 m/s^2 and u = 0 m/s. The time will be,
[tex]39.9 = 0 + \dfrac {1}{2}\times 9.8\times t^2[/tex]
[tex]t = 2.85 \;\rm s[/tex]
The time required to reach the bagels is 2.85 seconds. But in this time, the distance traveled by Henrietta is given below.
[tex]D' = 2.85 \times 3.95[/tex]
[tex]D' = 11.2527 \;\rm m[/tex]
Hence the total distance traveled by Henrietta is given below.
Distance = 25.675 + 11.2527
Distance = 36.9325 m.
The speed of the bagel is calculated as given below.
Speed = Total Distance / Time
[tex]v = \dfrac {36.9325 }{2.85}[/tex]
[tex]v = 12.9 \;\rm m/s[/tex]
Hence we can conclude that the speed at which the bagel was thrown horizontally is 12.9 m/s.
Part B
The total distance traveled by Henrietta is 36.9325 m. At this distance, Henrietta catches the bagel from the window.
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https://brainly.com/question/7359669.
Find the distance between the cities. Assume that Earth is a sphere of radius 4000 miles and that the cities are on the same longitude (one city is due north of the other). (Round your answer to one decimal place.)
Answer: 20231.75km
Explanation: Assuming the earth is a sphere with a radius r, the formulae for calculating the distance between 2 points on the earth surface is given as
[tex]l=\frac{\pi r}{180} *\alpha[/tex]
l = distance between two points on the earth surface (km)
π = 22/7
r = radius of the earth = 4000miles =6437.376 km ( we will be using kilometer because that is the SI unit for distance)
α = angle between the two cities on the earth surface. For our question, α=180 because one of the city is north and the second city is in the opposite direction (due north of the first)
By slotting in the parameters into the foemulae, we have that
[tex]l = \frac{\frac{22}{7} * 6437.376 }{180} * 180 \\\\l={\frac{22}{7} * 6437.376\\\\\\l=20231.751km[/tex]
A small crane has a motor that exerts 2.41 times 10^7 Pa of pressure on a fluid chamber. If the piston has an area of 168 cm2 how much force does the piston exert?
Answer:
[tex]F = 4.05\times 10^{9}\ N[/tex]
Explanation:
Given:
Exerts pressure
[tex]p = 2.41\times 10^{7}\ Pa[/tex]
Piston has an area
[tex]A = 168\ cm^{2][/tex]
We need to find the force exerted by piston.
Solution:
Formula of pascals law's is given as:
[tex]p=\frac{F}{A}[/tex]
Where:
F = Force applied
P = Pressure exerted
A = Cross sectional area
Substitute force and area in pascal's formula.
[tex]2.4\times 10^{7}=\frac{F}{168}[/tex]
Using cross multiplication.
[tex]F = (2.41\times 10^{7})\times 168[/tex]
[tex]F = 404.88\times 10^{7}[/tex]
[tex]F = 4.05\times 10^{9}\ N[/tex]
Therefore, the force exerted by piston [tex]F = 4.05\times 10^{9}\ N[/tex]
The piston exerts a force of 404,880 Newtons when the motor exerts a pressure of 2.41 x 10⁷ Pa on a fluid chamber with a piston area of 168 cm².
To determine the force exerted by the piston, we use the formula:
Force (F) = Pressure (P) × Area (A)
Given:
Pressure (P) = 2.41 x 10⁷ PaArea (A) = 168 cm²First, convert the area from cm² to m²:
1 m² = 10,000 cm²
A = 168 cm² / 10,000 = 0.0168 m²
Now, calculate the force:
F = 2.41 × 10⁷ Pa × 0.0168 m²
F = 404,880 N
Thus, the piston exerts a force of 404,880 Newtons.
What evidence did Sir Isaac Newton use to support his particle explanation of light? Light reflects off metal surfaces. Light travels in a straight line, and it casts a shadow. Light produces an interference pattern. Light causes electrons to be emitted from a metal surface.
Answer:
Isaac Newton supported his particle explanation of light by stating that light causes electrons to be emitted from a metal surface.
Explanation: The emission of electrons from metal surfaces when light of sufficient frequency falls on them is known as photoelecteic effect. He discovered photoelectric effect in the 19th century.
His other theories of light like light travels in a straight line could not explain diffraction and reflection. It needed the support of light as a wave to proof it.
Answer:
light travels in a straight line, and it casts a shadow.
Explanation:
The frequency output of a digital MAP sensor is reading 114 Hz. What is the approximate engine vacuum?
Answer:bob
Explanation:bc bob
A statue is to be 'scaled down.' It will have its size changed without changing its shape. It starts with an initial volume of 3.25 m3 and ends up with a final volume of 1.00 m3 .
Answer:
The solution are in the explanation
Explanation:
Volume varies with the cube of the linear dimension
Ratio of volumes is 3:1, therefore the ratio of the linear dimensions is 3^(1/3):1 = 1.442:1
Smaller statue is 350/1.442 cm = 242.7 cm
C = pi*D, D is a linear dimension, so Ds = 50/1.442 = 34.67 cm
Area varies with the square of the linear dimension; so the ratio of the areas will be (1/3)^(2/3) = 0.48; the surface area of the smaller statue will be 0.48 that of the original
The mass of the model would vary directly with the volume, so the mass of the model will be 1/3 that of the original
If the masses of the models are the same, then the model must be made of a material 3x the density of that used for the original.
In mathematics, scaling down a shape involves reducing its size while keeping its shape unchanged. To scale down a statue, you need to determine the scale factor by dividing the final volume by the initial volume. Then, apply the scale factor to each dimension of the statue.
Explanation:In mathematics, scaling down a shape means reducing its size while keeping its shape unchanged. The process involves multiplying the dimensions of the shape by a scale factor less than 1.
In this case, the initial volume of the statue is 3.25 m3 and it needs to be scaled down to a final volume of 1.00 m3. To determine the scale factor, divide the final volume by the initial volume: 1.00/3.25 = 0.307.
Next, apply the scale factor to each dimension of the statue. If the dimensions of the statue were 2m x 2m x 2m, the scaled-down dimensions would be 2m x 2m x 2m x 0.307 = 0.614m x 0.614m x 0.614m.
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A motorist is driving at 20m/s when she sees that a traffic light 200m ahead has just turned red. She knows that this light stays red for 15s, and she wants to reach the light just as it turns green again. It takes her 1.0s to step on the brakes and begin slowing.
What is her speed as she reaches the light at the instant it turns green?
To stop just as the light turns green, the motorist needs to decelerate in a controlled manner. The effective time to cover the distance after seeing the red light is 14 seconds, disregarding the 1 second it takes to react and press the brakes. Therefore, as she reaches the traffic signal when it turns green, her speed is 0 m/s.
Explanation:This situation can be approached using the concept of kinematics in Physics. To solve it, we need to consider total time and total distance traveled. The motorist is driving towards the traffic light, which is 200m away, and the light stays green for 15 seconds. However, since it takes her 1 second to step on the brakes, effectively, she has 14 seconds to travel to the light.
Since she starts braking the car, she begins to decelerate. While decelerating, time is the only determinant of the distance covered, not the speed. As she reaches the light, the speed would be zero regardless of the initial speed or distance if the deceleration is constant. So, when the light turns green, her speed will be 0 m/s.
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A powerful motorcycle can accelerate from rest to 22.2 m/s (80 km/h) in only 3.42 s. What is its average acceleration?
Explanation:
We have equation of motion v = u + at
Initial velocity, u = 0 m/s
Final velocity, v = 22.2 m/s
Time, t = 3.42 s
Substituting
v = u + at
22.2 = 0 + a x 3.42
a = 6.49 m/s²
Acceleration is 6.49 m/s²
Average acceleration is 6.49 m/s²
The ratio of girls to boys in a an astronomy club was 1 : 8. There were 5 girls. How many total members were there in the club?
Answer:
45
Explanation:
If the ratio is 1 : 8 and there was 5 girls you would need to find the ratio of 5 girls to x amount of boys then add both genders together to find the total amount. You would need to multiply 8x5 to find the amount of boys.
8x5=40
Then add the five girls
40+5=45
A tractor drives down highway 71 at a steady 12 km/hr. A Subaru WRX passes it at a steady 96 km/hr (possibly with a police car following it). Which vehicle has the smallest net force on it? (assume that the road at this point is both level and straight)
Answer:
neither one has a net force on it
Explanation:
Both vehicles are moving at steady velocity hence the acceleration zero.
since acceleration is zero , the net force on it is zero. therefore neither one has a net force on it
A student starts from the hostel and goes to his friend's house and then to his school. A is the displacement vector from the hostel to his friend's house. B is the displacement vector from his friend's house to school, and C is the direct path from the hostel to school. Which of the following vector operations is correct for the displacement from the hostel to his friend's house?
A) A - B.
B) A + B.
C) C - B.
D) C + B.
Answer:[tex]\vec{C}-\vec{B}[/tex]
Explanation:
Given
[tex]\vec{A}[/tex] is displacement of student from Hostel to house
[tex]\vec{B}[/tex] is displacement of student from house to school
And [tex]\vec{C}[/tex] is displacement of student from Hostel to school
According to the triangle law of vector addition
If two vectors are acting on a body simultaneously that are shown by magnitude and direction by two sides of a triangle taken in order then the third side is the resultant of two vectors that are taken in opposite direction.
[tex]\vec{A}+\vec{B}=\vec{C}[/tex]
[tex]\vec{A}=\vec{C}-\vec{B}[/tex]
so option c is correct
a 800 kg roller coaster cart is accelerated by a constant net force over a distance of 10 meters, as shown in the graph below: determine the speed of the cart after being accelerated for 10.0 meters.
Answer:
vf = 22.36[m/s]
Explanation:
First we must understand the data given in the problem:
m = mass = 800 [kg]
F = force = 20000[N]
dx = displacement = 10[m]
From newton's second we know that the sum of forces must be equal to the product of mass by acceleration.
[tex]F = m*a\\20000 = 800*a\\a = 20000/800\\a = 25 [m/s^2][/tex]
With the calculated acceleration, we can use the kinematics equations.
[tex]v_{f} ^{2} =v_{o} ^{2}+2*a*dx\\ v_{o} = initial velocity = 0\\a = acceleration = 25[m/s^2]\\dx= displacement = 10[m]\\[/tex]
The key to using this equation is to clarify that the initial velocity is zero since the body is at rest, otherwise the initial velocity would be an initial data.
[tex]v_{f} =\sqrt{2*25*10} \\v_{f} =22.36[m/s][/tex]
Another way of solving this problem is by means of the definition of work and kinetic energy, where work is defined as the product of the force by the distance.
W =F*d
W = 20000*10
W = 200000[J]
Kinetic energy is equal to work, therefore the value calculated above is equal to:
[tex]E_{k}=W =0.5*m*v_{f}^{2} \\200000=0.5*800*v_{f}^{2}\\v_{f}=\sqrt{\frac{200000}{0.5*800} } \\v_{f}=22.36[m/s][/tex]
Answer:
(A) 22.4 m/s
Explanation: hope this helps !
An airplane is flying at 95.0 m/s when the engine is turned off. As it glides, it experiences a force of drag so that is slows down at -0.700 m/s2. How far in meters will it travel in 1.00 minute ?
Explanation:
We have equation of motion s = ut + 0.5 at²
Initial velocity, u = 95 m/s
Acceleration, a = -0.700 m/s²
Time, t = 1 minute = 60 seconds
Substituting
s = ut + 0.5 at²
s = 95 x 60 + 0.5 x -0.700 x 60²
s = 4440 m
Distance traveled is 4440 m
The airplane travels 4440 m in 1 minute
To find the distance the airplane will travel in 1.00 minute, use the equation d = [tex]vi * t + (1/2) * a * t^2[/tex]e, vi is the initial velocity, t is the time, and a is the acceleration. Substitute the given values into the equation and solve to find the distance.
Explanation:To find the distance the airplane will travel in 1.00 minute, we need to use the equation:
d = vi * t +[tex](1/2) * a * t^2[/tex]
Where:
d = distance traveled
vi = initial velocity
t = time
a = acceleration
Using the given values:
vi = 95.0 m/s (initial velocity)
a = -[tex]0.700 m/s^2[/tex] (deceleration)
t = 1.00 minute = 60 seconds
Now we can substitute the values into the equation:
d = (95.0 * 60) + (1/2) * [tex](-0.700) * (60^2)[/tex]
Solving this equation will give us the distance traveled by the airplane in 1.00 minute.
A 10kg block is attached to a light cord that is wrapped around the pulley of an electric motor. What is the power output of the motor..?
when it is pulling the block upward with an instantaneous speed of 3m/s and an upward acceleration of 2 m/s?
a)300W b)360 c)600 d)240 e)480
Answer:
Option B is correct.
Power = 360 W
Explanation:
Power = Work done/time
Work done = Force × distance moved through by the force
Power = Force × (distance moved through by the force/time)
(Distance moved through by the force/time) = velocity = 3 m/s
Power = Force × velocity
Force = ma
But the acceleration in this case is this acceleration + acceleration due to gravity because the force has to be overcoming the force of gravity to now move the object upward at 2 m/s²
a = (2 + g) (assume acceleration due to gravity = 10 m/s²
a = 2 + 10 = 12 m/s²
F = ma = 10 × 12 = 120 N
Power = F × v = 120 × 3 = 360 W
An 8.6 m, 267 kg uniform ladder rests against a smooth wall. The coefficient of static friction between the ladder and the ground is 0.53 , and the ladder makes a 32.7 ◦ angle with the ground. How far up the ladder can a 1068 kg person climb before the ladder begins to slip? The acceleration of gravity is 9.8 m/s 2 . Answer in units of m.
Answer:
[tex]r_{P}=2.58 m[/tex]
Explanation:
If we want to find how far up the ladder can a person climb before the ladder begins to slip, the total force in the y-direction and the total torque must be zero, it is an equilibrium condition.
So, let's start whit y-direction forces.
[tex]\Sigma F_{y}=0[/tex]
[tex]N_{L}-W_{L}-W_{P}=0[/tex]
NL is the normal forceWL is the weight of the ladderWP is the weight of the personSo, we can find the normal force:
[tex]N_{L}=m_{L}g+m_{P}g=g(m_{L}+m_{P})=9.8(267+1068)=13083 N[/tex]
We know that the friction force is the product of the coefficient of static friction times the normal force. Let's find it.
[tex]F_{f}=\mu N_{L}=0.53*13083=6934 N[/tex]
Referent to the x-direction forces, we can say that the total sum must be equal to zero too.
[tex]\Sigma F_{x}=0[/tex]
[tex] -N_{wall}+F_{f}=0[/tex]
[tex] N_{wall}=F_{f}=6934 N[/tex]
Where N(wall) is the normal force due to the wall. (negative direction)Now, as we said before, the total torque must be zero, so we have:
[tex]\Sum \tau=\tau_{wall}+\tau_{L}+\tau_{P}=0[/tex] (1)
We will choose the pivot point at the bottom of the ladder, then we have:
Each force acting on the ladder must be perpendicular to the ladder, so we need to use the components.
[tex]\tau_{wall}=r_{wall}*N_{wall}sin(32.7)=8.6*6934*sin(32.7)=32215.8Nm[/tex] (positive due to the counterclockwise rotation)
[tex]\tau_{L}=r_{L}*W_{L}sin(57.3)=(8.6/2)*2616.6*sin(57.3)=-9468.2 Nm[/tex] (negative due to the clockwise rotation)
[tex]\tau_{P}=r_{P}*W_{P}sin(57.3)=r_{P}*10466.4*sin(57.3)=-r_{P}8807.6 Nm[/tex] (negative due to the clockwise rotation)
We use 57.3° because is the angle between the ladder weight vector and the ladder surface, we use the same angle to the person.
Now we can use (1) to find the distance
[tex]\Sum \tau=\tau_{wall}+\tau_{L}+\tau_{P}=32215.8-9468.2-r_{P}8807.6=0[/tex]
Therefore [tex]r_{P}=2.58 m[/tex]
I hope it helps you!
Recoil is noticeable if we throw a heavy ball while standing on a skateboard. If instead we go through the throwing motion but hold onto the ball, without friction effects our net recoil will be
A) zero.
B) the same as before.
C) small, but noticeable.
Answer:
A) zero.
Explanation:
If we go through the throwing motion but still hold onto the ball, then there will be 2 events:
1. you undergo the throwing motion, giving the ball's acceleration
2. you decelerate the ball so you can still hold onto it
Event 1 and 2 roughly need the same energy, but with the opposite vector. The sum of energy used for both events should be zero so the net recoil will also be zero too.
According to ____, the ability to detect a stimulus depends not only on the intensity of the stimulus but also on other variables such as the level of noise in the system and your expectations.
Answer:
Signal detection theory
Explanation:
Signal detection theory states that stimulus ca be detected according to its intensity and a person's psychological and/or physical state. This means that we can notice things according to how strong they are but also, a person's characteristics like experience and physiological state like fatigue can affect the ability to detect them.
Because of this, the answer is that according to signal detection theory, the ability to detect a stimulus depends not only on the intensity of the stimulus but also on other variables such as the level of noise in the system and your expectations.
Final answer:
Signal detection theory explains how the ability to detect a stimulus is influenced by both the stimulus intensity and psychological factors such as motivation and expectations, with practical examples like air traffic control demonstrating its significance.
Explanation:
According to signal detection theory, the ability to detect a stimulus depends not only on the intensity of the stimulus but also on variables such as the level of noise in the system and your expectations. Factors such as motivation can shift our ability to discriminate between a true sensory stimulus and background noise. For example, expecting an important phone call may lead you to think you hear the phone ringing while taking a shower, even though it is not. Similarly, a mother might wake up to the quiet murmur of her baby amidst other sounds because she is motivated to detect that specific stimulus.
Signal detection theory is not only a concept of psychological interest but also has practical applications, such as improving the accuracy of air traffic controllers. They need to detect planes among many signals on the radar screen, demonstrating the relevance of this theory in safety-critical professions. Furthermore, the theory incorporates the notion of both absolute threshold and difference threshold (or just noticeable difference), emphasizing the role of sensory capabilities alongside psychological factors in perception.
In Fig. 23-45, a small circular hole of radius R = 1.80 cm has been cut in the middle of an infinite, flat, nonconducting surface that has uniform charge density σ = 4.50 pC/m2 . A z axis, with its origin at the hole’s center, is perpendicular to the surface. In unitvector notation, what is the electric field at point P at z = 2.56 cm?
Answer:
The electric field at point a =( 0.232N/c)k
Explanation:
E = E1+E2=(6/2Eo)K+(-6/2Eo)[1-(2/(sqrtz^2+R^2)k
E= 6z/2Eo(sqrtz^2+R^2)k
E= (4.5×10^-12)×(2.56×10^-2) /2(8.85×10^-12)sqrt(2.56×10^-2)^2+(1.30×10^-2)^2k
E= 1.152×10^-13/(1.77×10^-11)×(2.8×10^-2)k
E= 1.152×10^-13/(4.956×10^-13)k
E=( 0.232N/c)K
Suzy drops a rock from the roof of her house. Mary sees the rock pass her 2.7 m tall window in 0.129 sec. From how high above the top of the window was the rock dropped? The acceleration of gravity is 9.8 m/s 2 . Answer in units of m.
Answer:
h = 22.35 m
Explanation:
given,
initial speed of the rock,u = 0 m/s
length of the window,l = 2.7 m
time taken to cross the window,t = 0.129 s
Speed of the rock when it crosses the window
[tex]v = \dfrac{l}{t}[/tex]
[tex]v = \dfrac{2.7}{0.129}[/tex]
v = 20.93 m/s
height of the building above the window
using equation of motion
v² = u² + 2 g h
20.93² = 0² + 2 x 9.8 x h
h = 22.35 m
Hence, the height of the building above the top of window is equal to h = 22.35 m
Skid is floating in space 3 m from Mitch. Skid and his backpack have a combined mass 50 kg. Skid releases his 10 kg backpack, which reduces his mass. If the same gravitational force is to be maintained between them, what will be the new distance between Skid and Mitch.?
Answer:
Explanation:
attached below is the working to the question asked. I equated the two formulas because of the statement "If the same gravitational force is to be maintained between them" mentioned in the question. The new distance between them is 2.68m
The total number of stars in the observable universe is roughly equivalent to:
a. the number of grains of sand on all the beaches on Earth.
b. the number of grains of sand on Miami Beach.
c. infinity.
Answer:
The number of grains of sand on all the beaches on Earth
Explanation:
if we assume grain of sand has an average size , then the number of grains of sand on all the beaches on Earth is roughly [tex]7.5 \times 10^{18}[/tex]
The total number of stars in the observable universe is roughly equivalent to 1 billion trillion. which is roughly equal to the number of grains of sand on all the beaches on Earth.