Circular Motion Questions and Answers

A tire starts from rest and rolls without slipping downhill at a constant acceleration of 13.6 m/s2. The diameter of the tire is 170 cm.
(a) Find the angular acceleration of the tire.
(b) How long does it take for the tire to reach an angular speed of 51.2 radians per second?
Physics
Circular Motion
A tire starts from rest and rolls without slipping downhill at a constant acceleration of 13.6 m/s2. The diameter of the tire is 170 cm. (a) Find the angular acceleration of the tire. (b) How long does it take for the tire to reach an angular speed of 51.2 radians per second?
A figure skater glides along a circular path of radius 2.63 m.
(a) If she coasts around one half of the circle, find the magnitude of the displacement vector.

(b) If she coasts around one half of the circle, find what distance she skated.

(c) What is the magnitude of the displacement if she skates all the way around the circle?
Physics
Circular Motion
A figure skater glides along a circular path of radius 2.63 m. (a) If she coasts around one half of the circle, find the magnitude of the displacement vector. (b) If she coasts around one half of the circle, find what distance she skated. (c) What is the magnitude of the displacement if she skates all the way around the circle?
After 10.0 s, a spinning roulette wheel at the carnival has slowed down to an angular velocity of +1.94 rad/s. During this time, the wheel has an angular acceleration of - -5.45 rad/s2. To pay for the game with one star [10 pts] calculate part a. To win the game and another star [10 pts] calculate part b. 
a. Starting Angular velocity? b. Determine the angular displacement of the wheel?
Physics
Circular Motion
After 10.0 s, a spinning roulette wheel at the carnival has slowed down to an angular velocity of +1.94 rad/s. During this time, the wheel has an angular acceleration of - -5.45 rad/s2. To pay for the game with one star [10 pts] calculate part a. To win the game and another star [10 pts] calculate part b. a. Starting Angular velocity? b. Determine the angular displacement of the wheel?
A ball of mass m attached to a string swings in a vertical circle, as shown. What is the tension in the string when the ball is at the top of the circle?
(a) Fc+ mg
(b) Fc - mg
(c) 2Fc
(d) 2mg
Physics
Circular Motion
A ball of mass m attached to a string swings in a vertical circle, as shown. What is the tension in the string when the ball is at the top of the circle? (a) Fc+ mg (b) Fc - mg (c) 2Fc (d) 2mg
Problem 2: Two wires are tied to the 0.3 kg sphere shown in the Figure above in the right. The sphere revolves in a horizontal circle at a constant speed of 7.5 m/sec. Let's call T₁ the tension in the upper wire and let's call T₂ the tension in the lower wire. What is T₁ and T₂? Answer: T₁ = 14.2 N and Thottom=8.3 N.
Physics
Circular Motion
Problem 2: Two wires are tied to the 0.3 kg sphere shown in the Figure above in the right. The sphere revolves in a horizontal circle at a constant speed of 7.5 m/sec. Let's call T₁ the tension in the upper wire and let's call T₂ the tension in the lower wire. What is T₁ and T₂? Answer: T₁ = 14.2 N and Thottom=8.3 N.
A 2 kg mass is spun on a string in a horizontal circular path at a constant speed.
a. Draw the free-body diagram for the mass.
b. If the radius of the path is 0.5 m and the period of revolution is 0.25 s, what is the speed of the mass?
c. What force is keeping the mass in a circular path?
d. What is the net force acting on the mass in the horizontal direction?
Physics
Circular Motion
A 2 kg mass is spun on a string in a horizontal circular path at a constant speed. a. Draw the free-body diagram for the mass. b. If the radius of the path is 0.5 m and the period of revolution is 0.25 s, what is the speed of the mass? c. What force is keeping the mass in a circular path? d. What is the net force acting on the mass in the horizontal direction?
12 m/sec Problem 1: A small remote-controlled car with mass 1.6 kg moves at a constant speed of v= in a track formed by a vertical circle inside a hollow metal cylinder that has a radius of 5.00 m (see Figure above on the left). What is the magnitude of the normal force exerted on the car by the walls of the cylinder at (a) point A (bottom of the track) and (b) point B (top of the track)? Answer: N₁61.8 N and N= 30.4 N.
Physics
Circular Motion
12 m/sec Problem 1: A small remote-controlled car with mass 1.6 kg moves at a constant speed of v= in a track formed by a vertical circle inside a hollow metal cylinder that has a radius of 5.00 m (see Figure above on the left). What is the magnitude of the normal force exerted on the car by the walls of the cylinder at (a) point A (bottom of the track) and (b) point B (top of the track)? Answer: N₁61.8 N and N= 30.4 N.
7. (II) A car drives straight down toward the bottom of a valley and up the other side on a road whose
bottom has a radius of curvature of 115 m. At the very bottom, the normal force on the driver is twice
his weight. At what speed was the car traveling?
Physics
Circular Motion
7. (II) A car drives straight down toward the bottom of a valley and up the other side on a road whose bottom has a radius of curvature of 115 m. At the very bottom, the normal force on the driver is twice his weight. At what speed was the car traveling?
A small lead ball, attached to a 1.45-m rope is being whirled in a circle that lies in the vertical plane. The ball is whirled at a constant rate of three revolutions per second and is released on the upward part of the circular path motion when it is 1.7m above the ground. The ball travels straight upward. In the absence of air resistance, to what max. height above the ground does the ball rise?
Physics
Circular Motion
A small lead ball, attached to a 1.45-m rope is being whirled in a circle that lies in the vertical plane. The ball is whirled at a constant rate of three revolutions per second and is released on the upward part of the circular path motion when it is 1.7m above the ground. The ball travels straight upward. In the absence of air resistance, to what max. height above the ground does the ball rise?
A toy car drives around a circular track with a radius of 10 m. When the car's velocity is instantaneously directed south, its acceleration is directed west at 10 m/s2. When viewed from above, the car moves (A) clockwise at 1 rad/s. (B) clockwise at 10 rad/s. (C) counterclockwise at 1 rad/s. (D) counterclockwise at 10 rad/s. (E) with constant velocity.
Physics
Circular Motion
A toy car drives around a circular track with a radius of 10 m. When the car's velocity is instantaneously directed south, its acceleration is directed west at 10 m/s2. When viewed from above, the car moves (A) clockwise at 1 rad/s. (B) clockwise at 10 rad/s. (C) counterclockwise at 1 rad/s. (D) counterclockwise at 10 rad/s. (E) with constant velocity.
A ring of mass m and radius R is performing pure rolling on inclined plane as shown, find direction of friction.
A. upward the inclined plane
B. downward the inclined plane
C. no friction acts
D. none of these
Physics
Circular Motion
A ring of mass m and radius R is performing pure rolling on inclined plane as shown, find direction of friction. A. upward the inclined plane B. downward the inclined plane C. no friction acts D. none of these
In order to simulate weightlessness for astronauts in training, they are flown in a vertical circle. If the passengers are to experience weightlessness, how fast should an airplane be moving at the top of a vertical
circle with a radius of 2.5 km?
A. 79 m/s
B. 510 m/s
C. 260 m/s
D. 310 m/s
E. 160 m/s
Physics
Circular Motion
In order to simulate weightlessness for astronauts in training, they are flown in a vertical circle. If the passengers are to experience weightlessness, how fast should an airplane be moving at the top of a vertical circle with a radius of 2.5 km? A. 79 m/s B. 510 m/s C. 260 m/s D. 310 m/s E. 160 m/s
What is the magnitude of the gravitational force of attraction between two 0.425-kilogram soccer balls when the distance between their centers is 0.461 meter?
(1) 2.41 × 10-¹¹ N
(2) 4.82 x 10-¹1 N
(3) 5.67 x 10-¹¹ N
(4) 1.13 × 10-¹0 N
Physics
Circular Motion
What is the magnitude of the gravitational force of attraction between two 0.425-kilogram soccer balls when the distance between their centers is 0.461 meter? (1) 2.41 × 10-¹¹ N (2) 4.82 x 10-¹1 N (3) 5.67 x 10-¹¹ N (4) 1.13 × 10-¹0 N
1. If the center of our moon is 384,400,000 m away from the center of Earth, how much force is needed to keep the moon in orbit around Earth? We previously found the moon to be moving at 1020 m/s relative to Earth and the mass of the moon is 7.35 x 10^22 kg. 

• Speed in a circle - m/s, how fast... 
• Radius - m, distance from the center of the circle to the object moving in the circle 
• Mass - kg, how much stuff something is made of 
• Centripetal Force - N, the force needed to keep an object moving in a circle 

Which variable is 1020 m/s?
Physics
Circular Motion
1. If the center of our moon is 384,400,000 m away from the center of Earth, how much force is needed to keep the moon in orbit around Earth? We previously found the moon to be moving at 1020 m/s relative to Earth and the mass of the moon is 7.35 x 10^22 kg. • Speed in a circle - m/s, how fast... • Radius - m, distance from the center of the circle to the object moving in the circle • Mass - kg, how much stuff something is made of • Centripetal Force - N, the force needed to keep an object moving in a circle Which variable is 1020 m/s?
Two blocks, with masses mA and mB, are connected to each other and to a central post by thin rods as shown in Fig. 5-41. The blocks revolve about the post at the same frequency f (revolutions per second) on a frictionless horizontal surface at distances A and B from the post. Derive an algebraic expression for the tension in each rod.
Physics
Circular Motion
Two blocks, with masses mA and mB, are connected to each other and to a central post by thin rods as shown in Fig. 5-41. The blocks revolve about the post at the same frequency f (revolutions per second) on a frictionless horizontal surface at distances A and B from the post. Derive an algebraic expression for the tension in each rod.
The arm of a crane at a construction site 100 m long, and it makes an angle of 10.3 with the horizontal. Assume that the max imum load the crane can handle is limite. by the amount of torque the load produce around the base of the arm. What maximum torque can the crane with- stand if the maximum load the crane car handle is 883 N? Answer in units of N · m.
Physics
Circular Motion
The arm of a crane at a construction site 100 m long, and it makes an angle of 10.3 with the horizontal. Assume that the max imum load the crane can handle is limite. by the amount of torque the load produce around the base of the arm. What maximum torque can the crane with- stand if the maximum load the crane car handle is 883 N? Answer in units of N · m.
For a car traveling at a certain speed, it is possible to bank a curve at just the right angle so that no friction at all is needed to maintain the car's turning radius. Then a can safely round the curve even on wet ice. Your engineering firm built a curve so that a car moving at a speed v can safely make the turn even with no friction. 1) At what angle 3 should the curve be banked? (Express it using v, free fall acceleration g, and radius of the curve R.) 2) When the car travels in the banked curve with speed v, what's the direction of the net force (vector sum of all the forces) applied to the car? (The curved is banked and the road on the is on the horizontal plane).
Physics
Circular Motion
For a car traveling at a certain speed, it is possible to bank a curve at just the right angle so that no friction at all is needed to maintain the car's turning radius. Then a can safely round the curve even on wet ice. Your engineering firm built a curve so that a car moving at a speed v can safely make the turn even with no friction. 1) At what angle 3 should the curve be banked? (Express it using v, free fall acceleration g, and radius of the curve R.) 2) When the car travels in the banked curve with speed v, what's the direction of the net force (vector sum of all the forces) applied to the car? (The curved is banked and the road on the is on the horizontal plane).
The diagram below shows a 5.0-kilogram bucket of water being swung in a horizontal circle of 0.50-meter radius at a constant speed of 2.0 meters per second. The magnitude of the centripetal force on the bucket of water is approximately * 
5.7 N
29 N
40 N
200 N
Physics
Circular Motion
The diagram below shows a 5.0-kilogram bucket of water being swung in a horizontal circle of 0.50-meter radius at a constant speed of 2.0 meters per second. The magnitude of the centripetal force on the bucket of water is approximately * 5.7 N 29 N 40 N 200 N
A 1,200-kilogram car traveling at a constant speed of 9.0 meters per second turns at an intersection. The car follows a horizontal circular path with a radius of 81 meters. The magnitude of the centripetal force acting on the car as it travels around the circular path is approximately * 
 11,000 N
 1,200 N
 3,900 N
 430 N
Physics
Circular Motion
A 1,200-kilogram car traveling at a constant speed of 9.0 meters per second turns at an intersection. The car follows a horizontal circular path with a radius of 81 meters. The magnitude of the centripetal force acting on the car as it travels around the circular path is approximately * 11,000 N 1,200 N 3,900 N 430 N
John Glenn was the first American to orbit Earth. In 1962, he circled Earth counterclockwise three times in less that 5 h aboard his spaceship Friendship 7. If his distance from the Earth's center was 6560 km, what arc length did Glenn and his spaceship travel through?
Physics
Circular Motion
John Glenn was the first American to orbit Earth. In 1962, he circled Earth counterclockwise three times in less that 5 h aboard his spaceship Friendship 7. If his distance from the Earth's center was 6560 km, what arc length did Glenn and his spaceship travel through?
A string can withstand a force of 135 N before breaking. A 2.0 kg mass is tied to the string and whirled in a horizontal circle with a radius of 1.10 m. What is speed that the mass can be whirled at before the string reaks? What was the centripetal acceleration of the mass?
Physics
Circular Motion
A string can withstand a force of 135 N before breaking. A 2.0 kg mass is tied to the string and whirled in a horizontal circle with a radius of 1.10 m. What is speed that the mass can be whirled at before the string reaks? What was the centripetal acceleration of the mass?
A motorcycle has a constant speed of 25.0 m/s as it passes over the top of a hill whose radius of curvature is 126 m. The mass of the motorcycle and driver is 342 kg. Find the magnitudes of (a) the centripetal force and (b) the normal force that acts on the cycle.
Physics
Circular Motion
A motorcycle has a constant speed of 25.0 m/s as it passes over the top of a hill whose radius of curvature is 126 m. The mass of the motorcycle and driver is 342 kg. Find the magnitudes of (a) the centripetal force and (b) the normal force that acts on the cycle.
On a flat, level road, a 1500-kilogram car travels around a curve having a constant radius of 25 meters. The centripetal acceleration of the car has a constant magnitude of 4.0 meters per second squared. Calculate the car's speed as it travels around the curve. 
 6.3 m/s
 10. m/s
 12 m/s
 15 m/s
Physics
Circular Motion
On a flat, level road, a 1500-kilogram car travels around a curve having a constant radius of 25 meters. The centripetal acceleration of the car has a constant magnitude of 4.0 meters per second squared. Calculate the car's speed as it travels around the curve. 6.3 m/s 10. m/s 12 m/s 15 m/s
A small plane makes a complete circle with a radius of 4,500 m in 90. seconds. What is the centripetal acceleration of the plane? *
22 meters per second squared
5.0 meters per second squared
16 meters per second squared
50. meters per second squared
Physics
Circular Motion
A small plane makes a complete circle with a radius of 4,500 m in 90. seconds. What is the centripetal acceleration of the plane? * 22 meters per second squared 5.0 meters per second squared 16 meters per second squared 50. meters per second squared
A trolley is curving at a 523 cm radius in the road at a speed of 28.0 m/s. If the centripetal force exerted on the trolley is 77.2 N, what is the trolley's mass? What is its centripetal acceleration?
Physics
Circular Motion
A trolley is curving at a 523 cm radius in the road at a speed of 28.0 m/s. If the centripetal force exerted on the trolley is 77.2 N, what is the trolley's mass? What is its centripetal acceleration?
An athlete whirls in a 7kg hammer tied to the end of a 1.3m chain in a horizontal circle. The hammer makes 1 revolution in 1 sec. What is the centripetal acceleration of the hammer and what is the tension in the chain?
Physics
Circular Motion
An athlete whirls in a 7kg hammer tied to the end of a 1.3m chain in a horizontal circle. The hammer makes 1 revolution in 1 sec. What is the centripetal acceleration of the hammer and what is the tension in the chain?
A phonograph record 30.0 cm in diameter rotates 33.5 times per minute. What is
(A)its frequency
(B)its period
(C)the linear speed of a point on its rim
(D)the centripetal acceleration of a point on its rim
Physics
Circular Motion
A phonograph record 30.0 cm in diameter rotates 33.5 times per minute. What is (A)its frequency (B)its period (C)the linear speed of a point on its rim (D)the centripetal acceleration of a point on its rim
A ball is thrown into the air at some angle. At the very top of the ball's path, its velocity is
Select one:
a. both vertical and horizontal.
b. entirely horizontal.
c. entirely vertical.
d. There's not enough information given to determine.
Physics
Circular Motion
A ball is thrown into the air at some angle. At the very top of the ball's path, its velocity is Select one: a. both vertical and horizontal. b. entirely horizontal. c. entirely vertical. d. There's not enough information given to determine.
The tub of a washer goes into its spin-dry cycle at an angular acceleration of 2 rad/s2, starting from rest during 10 s. At this point the person doing the laundry opens the lid, and a safety switch turns off the washer. The tub slows to rest in 8 s. Through how many revolutions does the tub turn during this 18 s interval? Assume constant angular acceleration while it is stopping.
Physics
Circular Motion
The tub of a washer goes into its spin-dry cycle at an angular acceleration of 2 rad/s2, starting from rest during 10 s. At this point the person doing the laundry opens the lid, and a safety switch turns off the washer. The tub slows to rest in 8 s. Through how many revolutions does the tub turn during this 18 s interval? Assume constant angular acceleration while it is stopping.
A swing consists of a metal circle with a pivot at the top of the circle. The seat is directly below the pivot when the swing is stil L. If the swing itself has a mass of 30 kg and a diameter of 2.0 m and a child of mass 38 kg sits on the seat, what will be the fre quency of the swing? i Hz Save for Later Submit Answer
Physics
Circular Motion
A swing consists of a metal circle with a pivot at the top of the circle. The seat is directly below the pivot when the swing is stil L. If the swing itself has a mass of 30 kg and a diameter of 2.0 m and a child of mass 38 kg sits on the seat, what will be the fre quency of the swing? i Hz Save for Later Submit Answer
An object is swung in a horizontal circle, starting at position zero (0 rad) and ends at 8 rad. If it has an initial angular velocity of 0 rad/s and an acceleration of 1.2 rad/s², what is its final angular velocity?
Physics
Circular Motion
An object is swung in a horizontal circle, starting at position zero (0 rad) and ends at 8 rad. If it has an initial angular velocity of 0 rad/s and an acceleration of 1.2 rad/s², what is its final angular velocity?
According to the shop manual, when drilling a 11.0-mm-diameter hole in wood, plastic, or aluminum, a drill should have a speed of 1300 rev/min
For a 11.0-mm-diameter drill bit turning at a constant 1300 rev/min, find the maximum linear speed of any part of the bit.
Find the maximum radial acceleration of any part of the bit.
Physics
Circular Motion
According to the shop manual, when drilling a 11.0-mm-diameter hole in wood, plastic, or aluminum, a drill should have a speed of 1300 rev/min For a 11.0-mm-diameter drill bit turning at a constant 1300 rev/min, find the maximum linear speed of any part of the bit. Find the maximum radial acceleration of any part of the bit.
A merry-go-round with radius R and moment of inertia ICM, that can freely rotate on a frictionless vertical axle, is initially at rest. A person with mass m is initially standing at the edge of the merry- go-round, and is also initially at rest. The person begins walking counter clockwise around the edge of the merry-go-round such that the (constant) speed of the person relative to the merry-go- round is Urel. Answer the following questions:
(A) What is u, the speed of the person relative to the ground? Express your answer in terms of Urel, m, R, and ICM. DRAW A BOX AROUND YOUR FINAL ANSWER.
Physics
Circular Motion
A merry-go-round with radius R and moment of inertia ICM, that can freely rotate on a frictionless vertical axle, is initially at rest. A person with mass m is initially standing at the edge of the merry- go-round, and is also initially at rest. The person begins walking counter clockwise around the edge of the merry-go-round such that the (constant) speed of the person relative to the merry-go- round is Urel. Answer the following questions: (A) What is u, the speed of the person relative to the ground? Express your answer in terms of Urel, m, R, and ICM. DRAW A BOX AROUND YOUR FINAL ANSWER.
An online video daredevil is filming a scene where he swings across a river on a vine. The safety crew must use a vine with enough strength so that it doesn't break while swinging. The daredevil's mass is 80.0 kg, the vine is 12.0 m long, and the speed of the daredevil at the bottom of the swing has been determined to be 8.20 m/s. What is the minimum tension force (in N) the vine must be able to support without breaking?
Physics
Circular Motion
An online video daredevil is filming a scene where he swings across a river on a vine. The safety crew must use a vine with enough strength so that it doesn't break while swinging. The daredevil's mass is 80.0 kg, the vine is 12.0 m long, and the speed of the daredevil at the bottom of the swing has been determined to be 8.20 m/s. What is the minimum tension force (in N) the vine must be able to support without breaking?
A spring harness entertains infants while keeping them from wandering. You notice that a child naturally bounces in their harness 4.0 times a second, following simple harmonic motion. If the child stops, crouches down and pushes off, when will the child next be falling at its fastest speed?
Physics
Circular Motion
A spring harness entertains infants while keeping them from wandering. You notice that a child naturally bounces in their harness 4.0 times a second, following simple harmonic motion. If the child stops, crouches down and pushes off, when will the child next be falling at its fastest speed?
It takes Stella Lyve 14.3 seconds to drive her 615 kg racing car at a constant speed around a circular track of 50.0 m radius.
a. What is the car's rate of acceleration?
b. What direction is the acceleration?
c. force is the force acting towards the center of the circle.
d. What is the amount of the inward force on the car?
Physics
Circular Motion
It takes Stella Lyve 14.3 seconds to drive her 615 kg racing car at a constant speed around a circular track of 50.0 m radius. a. What is the car's rate of acceleration? b. What direction is the acceleration? c. force is the force acting towards the center of the circle. d. What is the amount of the inward force on the car?
What is the angular speed of ladybug 1?
one-half the angular speed of ladybug 2
the same as the angular speed of ladybug 2
Otwice the angular speed of ladybug 2
one-quarter the angular speed of ladybug 2
Physics
Circular Motion
What is the angular speed of ladybug 1? one-half the angular speed of ladybug 2 the same as the angular speed of ladybug 2 Otwice the angular speed of ladybug 2 one-quarter the angular speed of ladybug 2
A 0.015 kg rubber stopper is attached to a 0.716 m length of string. The stopper is swung in a horizontal circle, making one revolution in 0.61 seconds. Find the stopper's velocity (v).
Physics
Circular Motion
A 0.015 kg rubber stopper is attached to a 0.716 m length of string. The stopper is swung in a horizontal circle, making one revolution in 0.61 seconds. Find the stopper's velocity (v).
Norman Neutron swings a rubber ball attached to a string over his head in a horizontal circular path. The string is 1.5 m long and the ball takes 0.5 seconds to go around once. What is the ball's velocity?
A. vt = 2πr/T
B. vt = √acr
C. Vt = √Fcr/m
D. Vc = mac
Physics
Circular Motion
Norman Neutron swings a rubber ball attached to a string over his head in a horizontal circular path. The string is 1.5 m long and the ball takes 0.5 seconds to go around once. What is the ball's velocity? A. vt = 2πr/T B. vt = √acr C. Vt = √Fcr/m D. Vc = mac
An object is rotating around an axis with a constant speed of 6.0 m/s, at a radius of 4.0 m.
What is the centripetal acceleration of the object?
A. 9.0 m/s² outward
B. 9.0 m/s² inward
C. 1.5 m/s2 outward
D. 1.5 m/s2 inward
Physics
Circular Motion
An object is rotating around an axis with a constant speed of 6.0 m/s, at a radius of 4.0 m. What is the centripetal acceleration of the object? A. 9.0 m/s² outward B. 9.0 m/s² inward C. 1.5 m/s2 outward D. 1.5 m/s2 inward