Question 1

The maximum speed around a level curve is 30. mi/h. What is the maximum speed around a curve with twice the radius? (Assume all other factors remain unchanged.)

Accepted Answer

A)  120. mi/h 
B)  42. mi/h 
C)  21. mi/h 
D)  60. mi/h 
E)  45. mi/h 
A)  120. mi/h 
B)  42. mi/h 
C)  21. mi/h 
D)  60. mi/h 
E)  45. mi/h B

Question 2

What is the angular speed of a point on the earth's surface at 60.0° north latitude? What is the linear speed of such a point?

Accepted Answer

7.27 × 10^-5 rad/s ; 0.232 km/s

Question 3

A satellite is in a low circular orbit about the Earth (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around the Earth?

Accepted Answer

87 min

Question 4

Jenny drives at a constant speed of 15. m/s around a circular drive of diameter 60. meters.
(a) Her acceleration is ________ m/s2.
(b) Is her acceleration tangential, centripetal, or centrifugal?
(c) Is her velocity tangential, centripetal, or centrifugal?

Accepted Answer

(a) 7.5 m/

Question 5

If the newly discovered planet of Krypton has 100. times the mass of the Earth and 100. times the diameter of the Earth, what would be the period of a "low" orbiting satellite around Krypton?

Accepted Answer

A)  0.15 hours 
B)  15. hours 
C)  1.5 × 102 hours 
D)  1.5 × 103 hours 
E)  1.5 hours 
A)  0.15 hours 
B)  15. hours 
C)  1.5 × 102 hours 
D)  1.5 × 103 hours 
E)  1.5 hours

Question 6

David lands on planet X and observes objects free-falling with acceleration 4.9 m/s2 s2 . If the planet is 3 times larger than the Earth, what is the planet MASS expressed in Earth masses?

Accepted Answer

A)  1/2 
B)  3/2 
C)  2/3 
D)  9/2 
E)  9/4 
A)  1/2 
B)  3/2 
C)  2/3 
D)  9/2 
E)  9/4

Question 7

By how many Newtons does the weight of a 100. kg person change when he goes from sea level to an altitude of 5.00 km?

Accepted Answer

The answer of By how many Newtons does the weight...

Question 8

The diameter of the sun is 13.9 × 108 m, and the distance from the Earth to the sun is 1.5 × 1011 m. How long does it take for the sun to disappear after it touches the horizon?

Accepted Answer

Question 9

The maximum acceleration a pilot can stand is about 7.0 g. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can tolerate at a speed of 250 m/s?

Accepted Answer

The answer of The maximum acceleration a pilot can stand...

Question 10

A car, driven around a circle with constant speed, must have

Accepted Answer

A)  a tangential acceleration. 
B)  zero acceleration. 
C)  zero velocity. 
D)  a centripetal acceleration. 
E)  a centrifugal acceleration. 
A)  a tangential acceleration. 
B)  zero acceleration. 
C)  zero velocity. 
D)  a centripetal acceleration. 
E)  a centrifugal acceleration.

Question 11

Consider an Earth satellite in an elliptical orbit. Its centripetal acceleration is

Accepted Answer

A)  constant. 
B)  zero. 
C)   g at the satellite. 
A)  constant. 
B)  zero. 
C)   g at the satellite.

Question 12

A satellite orbits the Earth once every 6.0 hours in a circle. What is the radius of the orbit if it is a 2000. Kg satellite?

Accepted Answer

The answer of A satellite orbits the Earth once every...

Question 13

A pulsar (a rotating neutron star) emits pulses at a frequency of 0.40 kHz. The period of its rotation is

Accepted Answer

A)  0.25 s. 
B)  2.5 s. 
C)  25 ms. 
D)  2.5 ms. 
E)  0.025 s. 
A)  0.25 s. 
B)  2.5 s. 
C)  25 ms. 
D)  2.5 ms. 
E)  0.025 s.

Question 14

A coin of mass m rests on a turntable a distance r from the axis of rotation. The turntable rotates with frequency f. Derive an expression for the minimum coefficient of friction between the turntable and the coin if the coin is not to slip.

Accepted Answer

The answer of A coin of mass m rests on...

Question 15

A 63. kg astronaut walks upon the surface of the planet Krypton which has 100. times the mass of the Earth and 100. times the diameter of the Earth. What does she weigh on Krypton?

Accepted Answer

63.× 9.8 ×

Question 16

An Earth satellite is in circular orbit 230 km above the surface of the Earth. It is observed to have a period of 89 min. From this information, estimate the mass of the Earth.

Accepted Answer

The answer of An Earth satellite is in circular orbit...

Question 17

A horizontal curve on a bobsled run is banked at a 45° angle. When a bobsled rounds this curve at the curve's safe speed (no friction needed to stay on the run), what is its centripetal acceleration?

Accepted Answer

A)  g /
  
B)  0.5 g 
C)  2.0 g 
D)    g 
E)  1.0 g 
A)  g /
  
B)  0.5 g 
C)  2.0 g 
D)    g 
E)  1.0 g

Question 18

A turntable was revolving at 33 1/3 rpm. It was shut off and uniformly slowed down and stopped in 5.5 seconds.
(a) What was the angular acceleration?
(b) Through how many revolutions did it turn?

Accepted Answer

(a) -0.10 rev/s² = -0

Question 19

The following statements refer to man-made, artificial satellites in orbit around Earth. Which is an accurate statement?

Accepted Answer

A)  The velocity required to keep a satellite in a given orbit depends on the mass of the satellite. 
B)  Only circular orbits are possible for artificial satellites. 
C)  The period of revolution of a satellite moving about the Earth is independent of the size of the orbit it travels. 
D)  A satellite in a large diameter circular orbit will always have a longer period of revolution about the Earth than will a satellite in a smaller circular orbit. 
E)  It is possible to have a satellite traveling at either a high speed or at a low speed in a given circular orbit. 
A)  The velocity required to keep a satellite in a given orbit depends on the mass of the satellite. 
B)  Only circular orbits are possible for artificial satellites. 
C)  The period of revolution of a satellite moving about the Earth is independent of the size of the orbit it travels. 
D)  A satellite in a large diameter circular orbit will always have a longer period of revolution about the Earth than will a satellite in a smaller circular orbit. 
E)  It is possible to have a satellite traveling at either a high speed or at a low speed in a given circular orbit.

Question 20

What is the angular speed in rad/s of an electric motor that rotates at 1.80 × 103 rpm?

Accepted Answer

Exam 7: Circular Motion and Gravitation

The maximum speed around a level curve is 30. mi/h. What is the maximum speed around a curve with twice the radius? (Assume all other factors remain unchanged.)

What is the angular speed of a point on the earth's surface at 60.0° north latitude? What is the linear speed of such a point?

A satellite is in a low circular orbit about the Earth (i.e., it just skims the surface of the Earth). How long does it take to make one revolution around the Earth?

Jenny drives at a constant speed of 15. m/s around a circular drive of diameter 60. meters. (a) Her acceleration is ________ m/s2. (b) Is her acceleration tangential, centripetal, or centrifugal? (c) Is her velocity tangential, centripetal, or centrifugal?

If the newly discovered planet of Krypton has 100. times the mass of the Earth and 100. times the diameter of the Earth, what would be the period of a "low" orbiting satellite around Krypton?

David lands on planet X and observes objects free-falling with acceleration 4.9 m/s2 s2 . If the planet is 3 times larger than the Earth, what is the planet MASS expressed in Earth masses?

By how many Newtons does the weight of a 100. kg person change when he goes from sea level to an altitude of 5.00 km?

The diameter of the sun is 13.9 × 108 m, and the distance from the Earth to the sun is 1.5 × 1011 m. How long does it take for the sun to disappear after it touches the horizon?

The maximum acceleration a pilot can stand is about 7.0 g. What is the minimum radius of curvature that a jet plane's pilot, pulling out of a vertical dive, can tolerate at a speed of 250 m/s?

A car, driven around a circle with constant speed, must have

Consider an Earth satellite in an elliptical orbit. Its centripetal acceleration is

A satellite orbits the Earth once every 6.0 hours in a circle. What is the radius of the orbit if it is a 2000. Kg satellite?

A pulsar (a rotating neutron star) emits pulses at a frequency of 0.40 kHz. The period of its rotation is

A coin of mass m rests on a turntable a distance r from the axis of rotation. The turntable rotates with frequency f. Derive an expression for the minimum coefficient of friction between the turntable and the coin if the coin is not to slip.

A 63. kg astronaut walks upon the surface of the planet Krypton which has 100. times the mass of the Earth and 100. times the diameter of the Earth. What does she weigh on Krypton?

An Earth satellite is in circular orbit 230 km above the surface of the Earth. It is observed to have a period of 89 min. From this information, estimate the mass of the Earth.

A horizontal curve on a bobsled run is banked at a 45° angle. When a bobsled rounds this curve at the curve's safe speed (no friction needed to stay on the run), what is its centripetal acceleration?

A turntable was revolving at 33 1/3 rpm. It was shut off and uniformly slowed down and stopped in 5.5 seconds. (a) What was the angular acceleration? (b) Through how many revolutions did it turn?

The following statements refer to man-made, artificial satellites in orbit around Earth. Which is an accurate statement?

What is the angular speed in rad/s of an electric motor that rotates at 1.80 × 103 rpm?

Measurement and Problem Solving

Kinematics: Description of Motion

Motion in Two Dimensions

Force and Motion

Work and Energy

Linear Momentum and Collisions

Rotational Motion and Equilibrium

Solids and Fluids

Temperature and Kinetic Theory

Heat

Thermodynamics

Vibrations and Waves

Sound

Electric Charge, Forces, and Fields

Electric Potential, Energy, and Capacitance

Electric Current and Resistance

Basic Electric Circuits

Magnetism

Electromagnetic Induction and Waves

AC Circuits

Reflection and Refraction of Light

Mirrors and Lenses

Physical Optics: The Wave Nature of Light

Vision and Optical Instruments

Relativity

Quantum Physics

Quantum Mechanics and Atomic Physics

The Nucleus

Nuclear Reactions and Elementary Particles

Filters

David lands on planet X and observes objects free-falling with acceleration 4.9 m/s^{2 s2}. If the planet is 3 times larger than the Earth, what is the planet MASS expressed in Earth masses?

The diameter of the sun is 13.9 × 10⁸ m, and the distance from the Earth to the sun is 1.5 × 10¹¹ m. How long does it take for the sun to disappear after it touches the horizon?

What is the angular speed in rad/s of an electric motor that rotates at 1.80 × 10³ rpm?