chapter 5

24) If a projectile is fired straight up at a speed of 10 m/s, the time it takes to reach the top of its path is about A) 1 s. B) 2 s. C) 10 s. D) not enough information given

A) 1 s.

20) A projectile is thrown into the air at an angle of 50° and lands on a target at a horizontal range. It will also land on the same target if it is thrown at an angle of _________ A) 40°. B) 45°. C) 55°. D) 60°.

A) 40°.

3) According to Newton, the greater the distance between masses of interacting objects, the gravitational force between them will A) be less B) be more C) remain the same D) None of the above

A) be less

23) An airplane flies at 40 m/s at an altitude of 50 m. The pilot drops a heavy package, which falls and strikes the ground. Where, approximately, does the package land? A) beneath the plane B) 400 m behind the plane C) 500 m behind the plane D) more than 500 m behind the plane

A) beneath the plane

5) If the mass of Earth somehow increased with no change in radius, your weight would A) increase also. B) decrease. C) stay the same. D) be none of the above

A) increase also

8) Your weight is A) the force due to gravity B) same as the mass of your body C) not related to the gravity of earth D) None of above

A) the force due to gravity

11) The gravity of planet Jupiter is much more than that of Earth. Your weight on Jupiter will be A. More than that on Earth B. less than that on Earth. C. same as that on Earth D. None of the above

A. More than that on Earth

18) A projectile is launched vertically at 50 m/s. If air resistance is negligible, its speed upon returning to its starting point is A) less than 50 m/s. B) 50 m/s. C) more than 50 m/s. D none of the above

B) 50 m/s.

6) Earth's gravitational field is A) only inside the Earth.. B) both inside and outside Earth. C) only on the surface of earth. D) none of the above

B) both inside and outside Earth.

15) What does "centripetal" mean? A) false force B) center-seeking force towards the center C) outward pull D) downward push

B) center-seeking force towards the center

2) According to Newton, the greater the masses of interacting objects, the A) less the gravitational force between them. B) greater the gravitational force between them. C) greater the force between them by the square of the masses. D) None of the above

B) greater the gravitational force between them.

17) A rock is thrown upward at 50° with respect to the horizontal. As it rises, its horizontal component of velocity A) increases. B) remains unchanged. C) decreases.

B) remains unchanged.

1) Newton discovered that A) gravity is a force on earth only B) that gravity is universal. C) Gravity is inertia on earth D) None of the above

B) that gravity is universal

28) If an object is projected above escape speed of earth, (11. 2 Km/s), the object A. will return to earth B. escape from earth and never return C remain stationary above earth None of the above

B. escape from earth and never return

22) After a rock that is thrown straight up reaches the top of its path when velocity becomes zero. While falling back down, its acceleration is------- A). zero B) more than 10 m/s2 C) 10 m/s2 D) less than 10 m/s2

C) 10 m/s2

4) What is the force of gravity on a 500-N woman standing on Earth's surface? A) 50 N B) 250 N C) 500 N D) 509.8 N E) none of the above

C) 500 N

10) A very massive object A and a less massive object B move toward each other under the influence of gravitation. Which force, if either, is greater? A) the force on A B) the force on B C) Both forces are the same. D. None of the above

C) Both forces are the same.

16) A rock is thrown upward at 50° with respect to the horizontal. As it rises, its vertical component of velocity A) increases. B) remains unchanged. C) decreases.

C) decreases.

9) Earth is revolving around the Sun because of the A) magnetic field around Earth. B) magnetic materials inside Earth C) force of attraction between Earth and Sun D) none of the above.

C) force of attraction between Earth and Sun

13) Which force is responsible for a space shuttle revolve around Earth? A) Normal force acting upwards B) support force. Acting upwards C) force of gravity D. none of the above

C) force of gravity

26) Communications and weather satellites always appear at the same place in the sky. This is because these satellites are A) beyond the pull of Earth's gravitational field. B) moving at a speed just short of escape velocity. C) orbiting Earth with a 24-hour period. D) stationary in space.

C) orbiting Earth with a 24-hour period.

25) A projectile is fired vertically from the surface of Earth at 10 km/s. The projectile will A) go into circular orbit about Earth. B) go into an elliptical orbit about Earth. C) rise and fall back to Earth's surface. D) none of the above

C) rise and fall back to Earth's surface.

21) A ball is thrown upward and caught when it comes back down. Neglecting air resistance, the speed with which it is caught is A) more than the speed it had when thrown upward. B) less than the speed it had when thrown upward. C) the same as the speed it had when thrown upward. D. None of the above

C) the same as the speed it had when thrown upward.

19) A projectile is launched at an angle of 15° above the horizontal and hits a target on ground at a horizontal range. What other projection angle for the same speed would produce the same horizontal range? A) 30° B) 45° C) 50° D) 75°

D) 75°

12) When falling under gravity a person will experience A) force of repulsion B) decrease in weight C) increase in weight D) Weightlessness

D) Weightlessness

27) What is escape speed? A) the speed for a body to maintain orbit B) the fastest speed an object can fall toward Earth C) close to the speed of light D) the speed required to leave a gravitational field

D) the speed required to leave a gravitational field

14) How far must one travel to get away from Earth's gravitational field? A) to a region above Earth's atmosphere B) to a region up to the Moon C) to 50 km above earth's surface D) you can't travel far enough.

D) you can't travel far enough.