1 Marks: 1 If a two-body collision is not head-on, then we may always assume that:Choose one answer.

a. momentum is conserved.

b. kinetic energy is conserved.

c. neither momentum nor kinetic energy are conserved.

d. both momentum and kinetic energy are conserved.

e. none of the above choices are valid. CorrectMarks for this submission: 1/1.Question 2 Marks: 1 A cannon of mass 1 500 kg fires a 10-kg shell with a velocity of 200 m/s at an angle of

above the horizontal. Find the recoil velocity of the cannon across the level ground. Choose one answer.

a. 1.33 m/s

b. 0.94 m/s

c. 2.41 m/s

d. 1.94 m/s

e. 0.87 m/s CorrectMarks for this submission: 1/1.Question 3 Marks: 1 A billiard ball is moving in the x-direction at 30.0 cm/s and strikes another billiard ball moving in the y-direction at 40.0 cm/s. As a result of the collision, the first ball moves at 50.0 cm/s, and the second ball stops. What is the change in kinetic energy of the system as a result of the collision?Choose one answer.

a. 0

b. some positive value

c. some negative value

d. No answer above is correct. CorrectMarks for this submission: 1/1.Question 4 Marks: 1 A billiard ball (Ball #1) moving at 5.00 m/s strikes a stationary ball (Ball #2) of the same mass. After the collision, Ball #1 moves at a speed of 4.35 m/s. Find the speed of Ball #2 after the collision.

Choose one answer.

a. 1.25 m/s

b. 1.44 m/s

c. 2.16 m/s

d. 2.47 m/s

e. 2.68 m/s CorrectMarks for this submission: 1/1.Question 5 Marks: 1 An 90-kg satellite orbits a distant planet with a radius of 4000 km and a period of 280 min. From the radius and period, you calculate the satellite's acceleration to be 0.56 m/s2. What is the gravitational force on the satellite?Choose one answer.

a. 50.4 N

b. 90 N

c. 720 N

d. 12,000 N CorrectMarks for this submission: 1/1.Question 6 Marks: 1 Al the astronaut has a weight of 800 N when he is standing on the surface of Earth. What is the force of gravity acting on him when he is in a space station orbiting Earth at a distance of three Earth radii above the surface?Choose one answer.

a. 800 N

b. 200 N

c. 100 N

d. 50 N CorrectMarks for this submission: 1/1.Question 7 Marks: 1 Does the Moon orbit the Sun?Choose one answer.

a. Yes. It goes in a circle about the Sun.

b. No. It orbits Earth.

c. Yes, but it also orbits Earth.

d. No, but it would if Earth were not present. IncorrectMarks for this submission: 0/1.Question 8 Marks: 1 An astronaut weighs 800 N when measured on Earth's surface. How large would his weight be if he were in a satellite at an altitude equal to Earth's radius?Choose one answer.

a. zero

b. less than 800 N

c. 800 N

d. more than 800 N CorrectMarks for this submission: 1/1.Question 9 Marks: 1 What happens to the total momentum of a star that undergoes a supernova explosion?Choose one answer.

a. It increases.

b. It remains constant.

c. It decreases.

d. It depends on the color of the star. CorrectMarks for this submission: 1/1.Question 10 Marks: 1 The gravitational constant G in the law of universal gravitationChoose one answer.

a. is believed to be constant with time.

b. is believed to have the same value throughout space.

c. leads to a determination of the mass of Earth.

d. All of the above are true. CorrectMarks for this submission: 1/1.

1 Marks: 1 A 0.12-kg ball is moving at 6 m/s when it is hit by a bat, causing it to reverse direction and have a speed of 14 m/s. What is the change in the magnitude of the momentum of the ball?Choose one answer.

a. 0.39 kg?m/s

b. 0.42 kg?m/s

c. 1.3 kg?m/s

d. 2.4 kg?m/s

e. 3.2 kg?m/s CorrectMarks for this submission: 1/1.Question 2 Marks: 1 Does the Moon orbit the Sun?Choose one answer.

a. Yes. It goes in a circle about the Sun.

b. No. It orbits Earth.

c. Yes, but it also orbits Earth.

d. No, but it would if Earth were not present. CorrectMarks for this submission: 1/1.Question 3 Marks: 1 The gravitational force between two metal spheres in outer space is 1000 N. How large would this force be if each of the two spheres had twice the mass?Choose one answer.

a. 1000 N

b. 2000 N

c. 4000 N

d. 16,000 N IncorrectMarks for this submission: 0/1.Question 4 Marks: 1 If an astronaut in full gear has a weight of 1200 N on Earth, how much will the astronaut weigh on the Moon?Choose one answer.

a. 20 N

b. 120 N

c. 200 N

d. 720 N CorrectMarks for this submission: 1/1.

Question 5 Marks: 1 Object 1 has twice the mass of Object 2. Each of the objects has the same magnitude of momentum. Which of the following statements is true?Choose one answer.

a. Both objects can have the same kinetic energy.

b. One object has 0.707 times the kinetic energy of the other.

c. One object has twice the kinetic energy of the other.

d. One object has 4 times the kinetic energy of the other.

e. None of the above choices are valid. IncorrectMarks for this submission: 0/1.Question 6 Marks: 1 If rockets are fired from an airplane in the forward direction, the momentum of the airplane willChoose one answer.

a. decrease.

b. be unchanged.

c. increase. CorrectMarks for this submission: 1/1.Question 7 Marks: 1 Two spacecraft in outer space attract each other with a force of 20 N. What would the attractive force be if they were one-half as far apart?Choose one answer.

a. 5 N

b. 10 N

c. 40 N

d. 80 N CorrectMarks for this submission: 1/1.Question 8 Marks: 1 A car wash nozzle directs a steady stream of water at 1.5 kg/s, with a speed of 30 m/s, against a car window. What force does the water exert on the glass? Assume the water does not splash back.Choose one answer.

a. 11 N

b. 45 N

c. 110 N

d. 440 N

e. 540 N CorrectMarks for this submission: 1/1.Question 9 Marks: 1 When a star undergoes a supernova explosion, the total linear momentum of the starChoose one answer.

a. does not change.

b. increases.

c. decreases. CorrectMarks for this submission: 1/1.Question 10 Marks: 1 If we imagine launching an apple into a circular orbit about Earth and ignore the effects of air resistance, we know that the apple will experienceChoose one answer.

a. a constant velocity.

b. no net force.

c. a force due to its inertia.

d. a centripetal force due to gravity. IncorrectMarks for this submission: 0/1.

1 Marks: 1 Neglecting gravity, doubling the exhaust velocity from a single stage rocket initially at rest changes the final velocity attainable by what factor? Assume all other variables, such as the mass of the rocket and the mass of the fuel, do not change.Choose one answer.

a. The final velocity stays the same.

b. The final velocity doubles.

c. The final velocity increases by a factor of 0.693.

d. The final velocity increases by a factor of 0.310.

e. None of the above choices are valid. IncorrectMarks for this submission: 0/1.Question 2

Marks: 1 Sally is an astronaut who has a mass of 60 kg. Currently she is conducting experiments in a permanent space station that is orbiting Earth at an altitude equal to Earth's radius. What is the force of gravity acting on Sally while she is in the space station?Choose one answer.

a. zero

b. 150 N

c. 300 N

d. 600 N CorrectMarks for this submission: 1/1.Question 3 Marks: 1 A car wash nozzle directs a steady stream of water at 1.5 kg/s, with a speed of 30 m/s, against a car window. What force does the water exert on the glass? Assume the water does not splash back.Choose one answer.

a. 11 N

b. 45 N

c. 110 N

d. 440 N

e. 540 N CorrectMarks for this submission: 1/1.Question 4 Marks: 1 A lump of clay is thrown at a wall. A rubber ball of identical mass is thrown with the same speed toward the same wall. Which statement is true?Choose one answer.

a. The clay experiences a greater change in momentum than the ball.

b. The ball experiences a greater change in momentum than the clay.

c. The clay and the ball experience the same change in momentum.

d. It is not possible to know which object has the greater change in momentum.

e. The clay doesn't change its momentum. CorrectMarks for this submission: 1/1.Question 5 Marks: 1 In a system with two moving objects, when a collision occurs between the objects:Choose one answer.

a. the total kinetic energy is always conserved.

b. the total momentum is always conserved.

c. the total kinetic energy and total momentum are always conserved.

d. neither the kinetic energy nor the momentum is conserved.

e. none of the above choices are valid. IncorrectMarks for this submission: 0/1.Question 6 Marks: 1 A model car is propelled by a cylinder of carbon dioxide gas. The cylinder emits gas at a rate of 4.5 g/s with an exit speed of 80.0 m/s. The car has a mass of 400 g, including the

cylinder. Starting from rest, what is the car's initial acceleration? Choose one answer.

a. 0.90

b. 4.5

c. 9.0

d. 36

e. 42 CorrectMarks for this submission: 1/1.Question 7 Marks: 1 What is the magnitude of Earth's gravitational field at a distance equal to twice Earth's radius?Choose one answer.

a. 20 N/kg

b. 10 N/kg

c. 5 N/kg

d. 2.5 N/kg IncorrectMarks for this submission: 0/1.Question 8 Marks: 1 An Earth satellite is orbiting at a distance from the Earth's surface equal to one Earth radius (4 000 miles). At this location, the acceleration due to gravity is what factor times the value of g at the Earth's surface?Choose one answer.

a. There is no acceleration since the satellite is in orbit.

b. 2

c. 1/2

d. 1/4

e. 4 CorrectMarks for this submission: 1/1.Question 9 Marks: 1 If Earth's mass were suddenly and magically reduced to half its present value, the magnitude of Earth's acceleration about the Sun wouldChoose one answer.

a. be reduced by a factor of 4.

b. be reduced by a factor of 2.

c. remain the same.

d. increase by a factor of 2. IncorrectMarks for this submission: 0/1.Question 10 Marks: 1 Over which of the following locations is it possible to have a synchronous satellite?Choose one answer.

a. New York City

b. Los Angeles

c. North Pole

d. equator CorrectMarks for this submission: 1/1.1 Marks: 1 A miniature spring-loaded, radio-controlled gun is mounted on an air puck. The gun's bullet has a mass of 5.00 g, and the gun and puck have a combined mass of 120 g. With the system initially at rest, the radio controlled trigger releases the bullet causing the puck and empty gun to move with a speed of 0.500 m/s. What is the bullet's speed?Choose one answer.

a. 4.80 m/s

b. 11.5 m/s

c. 48.0 m/s

d. 12.0 m/s

e. 23.0 m/s CorrectMarks for this submission: 1/1.

Question 2 Marks: 1 Which of the following statements about Venus is not correct?Choose one answer.

a. The Sun's gravitational pull on Venus equals Venus' gravitational pull on the Sun.

b. There is a net force acting on Venus.

c. Venus is accelerating toward the Sun.

d. There is no gravity on the surface of Venus. CorrectMarks for this submission: 1/1.Question 3 Marks: 1 Al the astronaut has a weight of 800 N when he is standing on the surface of Earth. What is the force of gravity acting on him when he is in a space station orbiting Earth at a distance of three Earth radii above the surface?Choose one answer.

a. 800 N

b. 200 N

c. 100 N

d. 50 N CorrectMarks for this submission: 1/1.Question 4 Marks: 1 Two moving objects collide, stick to each other, and move off together. Linear momentumChoose one answer.

a. is definitely conserved.

b. is definitely not conserved.

c. may or may not be conserved, depending on the nature of the collision.

d. none of the above. CorrectMarks for this submission: 1/1.Question 5 Marks: 1 A 20-kg object sitting at rest is struck elastically in a head-on collision with a 10-kg object initially moving at +3.0 m/s. Find the final velocity of the 20-kg object after the collision.Choose one answer.

a. ?1.0 m/s

b. ?2.0 m/s

c. +1.5 m/s

d. +2.0 m/s

e. ?1.5 m/s CorrectMarks for this submission: 1/1.Question 6 Marks: 1 Assume that a red car has a mass of 1000 kg and a white car has a mass of 2000 kg. If both cars are traveling at the same velocity,Choose one answer.

a. their kinetic energies are equal.

b. their momenta are equal.

c. the red car's kinetic energy is twice as big.

d. the white car's kinetic energy is twice as big. CorrectMarks for this submission: 1/1.Question 7 Marks: 1 An object of mass 0.50 kg is transported to the surface of Planet X where the object's

weight is measured to be 20 N. The radius of the planet is m. What is the

mass of Planet X? (G = ) Choose one answer.

a. kg

b. kg

c. kg

d. kg

e. kg CorrectMarks for this submission: 1/1.Question 8 Marks: 1

Given that the acceleration due to gravity on Mars is 3.7 , what is the gravitational field near Mar's surface? Choose one answer.

a. 3.7 N/kg

b. 3.7 N/kg up

c. 3.7 N/kg down

d. 10 N/kg down CorrectMarks for this submission: 1/1.Question 9 Marks: 1 Geosynchronous satellites orbit the Earth at a distance of 42 000 km from the Earth's center. Their angular speed at this height is the same as the rotation rate of the Earth, so they appear stationary at certain locations in the sky. What is the force acting on a 1 500-kg satellite at this height?Choose one answer.

a. 85 N

b. 333 N

c. 404 N

d. 457 N

e. 514 N CorrectMarks for this submission: 1/1.Question 10 Marks: 1 The kinetic energy of an object is quadrupled. Its momentum will change by what factor?Choose one answer.

a. zero

b. two

c. eight

d. four

e. None of the above. CorrectMarks for this submission: 1/1.