Q: A proton of mass $$1.67 \times 10$$^{-27}$$\ \mathrm{kg}$$ moves in a circle of diameter $$1.6\ \mathrm{m} at an $$angular speed of $$2.0 \times 10^6$\ \mathrm{rad/s}. $$What is the angular momentum of the proton?

$$2.67 \times 10$$^{-21}$$\ \mathrm{kg \cdot m^2$/s}$$

Q: Two small objects, each with mass $$2.0\ \mathrm{kg}$$, are separated by $$0.5\ \mathrm{m}. $$What is the magnitude of the gravitational force between them? ($$G = 6.67 \times 10$$^{-11}$$\ \mathrm{N \cdot m^2$/kg^2$$}$)

$$1.07 \times 10$$^{-9}$$\ \mathrm{N}$$

Q: Venus and Earth are $$1.08 \times 10$$^{11}$$\ \mathrm{m}$$ apart. The mass of Venus is $$4.87 \times 10$$^{24}$$\ \mathrm{kg}$$ and Earth is $$5.97 \times 10$$^{24}$$\ \mathrm{kg}. $$What is the gravitational force between them?

$$1.67 \times 10$$^{23}$$\ \mathrm{N}$$

Question 1

Two blocks, A (2 kg) and B (4 kg), move toward each other on a frictionless track. Block A moves at $$2.0\ \mathrm{m/s} to $$the right, and block B moves at $$1.0\ \mathrm{m/s} to $$the left. After they collide, block A moves at $$-0.5\ \mathrm{m/s}$$ and block B at $$1.0\ \mathrm{m/s}. $$What type of collision occurred?

Accepted Answer

Inelastic but not perfectly inelastic

Question 2

Three objects (10 kg, 5 kg, and 20 kg) move in a straight line with velocities $$2\ \mathrm{m/s}$$, $$-3\ \mathrm{m/s}$$, and $$0.5\ \mathrm{m/s}$$ respectively. What is the total momentum of the system?

Accepted Answer

$$7\ \mathrm{kg} \cdot \mathrm{m/s}$$

Question 3

A 1000 kg vehicle moving at $$8.0\ \mathrm{m/s}$$ collides with a stationary 200 kg cart. After the collision, the cart moves at $$10.0\ \mathrm{m/s}$$ and the vehicle slows to $$6.0\ \mathrm{m/s}. $$What is the total momentum after the collision?

Accepted Answer

$$8000\ \mathrm{kg} \cdot \mathrm{m/s}$$

Question 4

Which of the following statements about conservation of momentum is correct?

Accepted Answer

Momentum is conserved in both elastic and inelastic collisions.

Question 5

A block of mass $$3.4\ \mathrm{kg}$$ moving at $$1.2\ \mathrm{m/s}$$ collides with a stationary $$8.1\ \mathrm{kg}$$ block. After the collision, the $$3.4\ \mathrm{kg}$$ block moves at $$-0.50\ \mathrm{m/s}. $$What is the magnitude of the impulse on the $$3.4\ \mathrm{kg}$$ block?

Accepted Answer

$$5.8\ \mathrm{N \cdot s}$$

Question 6

A mass of $$6.0\ \mathrm{kg} is $$lifted to a height of $$0.5\ \mathrm{m}$$ and then dropped. What is its velocity just before hitting the ground? (Assume $$g = 9.8\ \mathrm{m/s^2$})$$

Accepted Answer

$$3.1\ \mathrm{m/s}$$

Question 7

A child sits on a merry-go-round that is turning at $$1.7\ \mathrm{rad/s}. $$The child is $$4.0\ \mathrm{m}$$ from the center. What is the child's tangential speed?

Accepted Answer

$$6.8\ \mathrm{m/s}$$

Question 8

A solid uniform sphere of mass $$120\ \mathrm{kg}$$ and radius $$1.7\ \mathrm{m}$$ rolls without slipping down a $$12\ \mathrm{m}$$ incline. What is its speed at the bottom?

Accepted Answer

$$7.7\ \mathrm{m/s}$$

Question 9

A scooter has wheels with a diameter of $$0.25\ \mathrm{m}. If $$the scooter moves forward at $$4.0\ \mathrm{m/s}$$, what is the angular speed of the wheels?

Accepted Answer

$$32\ \mathrm{rad/s}$$

Question 10

A force of $$15.8\ \mathrm{N} is $$applied tangentially to a wheel of radius $$0.340\ \mathrm{m}$$ and causes an angular acceleration of $$4.65\ \mathrm{$$rad/s^2$$}. $$What is the moment of inertia of the wheel?

Accepted Answer

$$1.16\ \mathrm{kg \cdot m^2$}$$

Question 11

A meter stick balances at the $$50.0\ \mathrm{cm}$$ mark. If a mass of $$50.0\ \mathrm{g} is $$placed at the $$96.0\ \mathrm{cm}$$ mark, where should a $$20.0\ \mathrm{g}$$ mass be placed to maintain the balance?

Accepted Answer

$$4.0\ \mathrm{cm}$$

Question 12

A proton of mass $$1.67 	imes 10$$^{-27}$$\ \mathrm{kg}$$ moves in a circle of diameter $$1.6\ \mathrm{m} at an $$angular speed of $$2.0 	imes 10^6$\ \mathrm{rad/s}. $$What is the angular momentum of the proton?

Accepted Answer

$$2.67 	imes 10$$^{-21}$$\ \mathrm{kg \cdot m^2$/s}$$

Question 13

Two small objects, each with mass $$2.0\ \mathrm{kg}$$, are separated by $$0.5\ \mathrm{m}. $$What is the magnitude of the gravitational force between them? ($$G = 6.67 	imes 10$$^{-11}$$\ \mathrm{N \cdot m^2$/kg^2$$}$)

Accepted Answer

$$1.07 	imes 10$$^{-9}$$\ \mathrm{N}$$

Question 14

Venus and Earth are $$1.08 	imes 10$$^{11}$$\ \mathrm{m}$$ apart. The mass of Venus is $$4.87 	imes 10$$^{24}$$\ \mathrm{kg}$$ and Earth is $$5.97 	imes 10$$^{24}$$\ \mathrm{kg}. $$What is the gravitational force between them?

Accepted Answer

$$1.67 	imes 10$$^{23}$$\ \mathrm{N}$$

Question 15

A hypothetical planet has mass $$M$$ and radius $$R. If $$the acceleration due to gravity at the surface is $$g$$, what is the acceleration due to gravity at a height $$2R$$ above the surface?

Accepted Answer

$$g/8$$

Question 16

A solid uniform disk of mass $$2.0\ \mathrm{kg}$$ and radius $$0.35\ \mathrm{m} is $$spun up to $$10.0\ \mathrm{rad/s}$$ and then allowed to come to rest over a distance of $$4.0\ \mathrm{m}$$ due to friction. What is the work done by friction?

Accepted Answer

$$24.5\ \mathrm{J}$$

Review Study Notes: Linear Momentum, Collisions, Rotational Motion, and Gravity (Chapters 9–12)

Study Guide - Practice Questions

Study Guide - Flashcards