# Newton's Laws : Quiz 3 Practice Questions

1.    A motorcycle of mass 100 kg travels around a flat, circular track of radius 10 m with a constant speed of 20 m/s.
What force is required to keep the motorcycle moving in a circular path at this speed ?
200 N          400 N          2000 N         4000 N

2.    A car going around a curve is acted upon by a centripetal force, F. If the speed of the car were twice as great,
the centripetal force necessary to keep it moving in the same path would be
F          2F          F/2         4F

3.    A motorcycle travels around a flat circular track. If the speed of the motorcycle is increased, the force required
to keep it in the same circular path
decreases          increases          remains the same

4.    As the distance between two masses increases, the gravitational force of attraction between them
decreases          increases          remains the same

5.    If the distance between two masses is tripled, the gravitational force between them becomes
1/9 as great          1/3 as great          3 times as great          9 times as great

6.    A rocket weighs 10,000 N at the earth's surface. If the rocket rises to a height equal to the earth's radius above the
earth's surface, its weight will be
2500 N          5000 N          10,000 N         40,000 N

7.    If the distance between two objects of constant mass is doubled, the gravitational force of attraction between them is

8.    An object weighing 20.0 N at the earth's surface is moved to an altitude where its weight is 10.0 N. The acceleration
due to gravity at this altitude is
2.45 m/s2          4.90 m/s2          9.80 m/s2          19.6 m/s2

9.    An object weighing 16 N at the earth's surface is moved above the earth a distance equal to the earth's radius. The
gravitational field strength at this new position is
2.5 N/kg          4.9 N/kg          9.8 N/kg          4.0 N/kg

10.    As the mass of a body increases, its gravitational force of attraction on the Earth
decreases          increases          remains the same

11.    The magnitude of the gravitational force between two objects is 20. N. If the mass of each object were doubled, the
magnitude of the gravitational force between the objects would be
5.0 N          10. N          20.N          80. N

12.    The gravitational force of attraction between two objects is 9.0 N. If the mass of one of the objects is tripled, the new
gravitational force of attraction will be
1.0 N          3.0 N          27 N          81 N

13.    The gravitational force of attraction between two objects is F. If the mass of each object is doubled, and the distance
between them is doubled, what is the new gravitational force of attraction ?
1/4 F          1/2 F          F          4 F