1. A 20.0-g bead is attached to a light 120 cm-long string, as shown in the figure. This bead moves in a horizontal circle with a constant speed. If the angle is measured to be 18, what is the speed of the bead? https://cdn.flvs.net/assessment_images/educator_apphysics_v23/03_10_a.jpg

0.55 m/s 1.1 m/s 2.0 m/s 3.8 m/s

2.What is the mass of an object that experiences a gravitational force of 924 N near Earth's surface where g = 9.80 m/s²?

72.7 kg 65.4 kg 71.3 kg 94.3 kg

3. In order to simulate weightlessness for astronauts in training, they are flown in a vertical circle. If the passengers are to experience weightlessness, how fast should an airplane be moving at the top of a vertical circle with a radius of 2.5 km?

79 m/s 310 m/s 260 m/s 160 m/s

4. Satellite B has three times the mass of satellite A and moves at the same orbital distance from Earth as satellite B. Compare the speeds of the two satellites.

The speed of A is equal to the speed of B. The speed of A is equal to 3 times the speed of B. The speed of A is 1/3 the speed of B. The speed of A is 1/6 the speed of B.

5. What is the gravitational force acting on a 59-kg person, due to another 59-kg person standing 2.0 m away? We can model each person as a small sphere. (G = 6.67 10-11N m²/kg²)

5.8 10^-8 N 8.5 10³ N 1.2 10^-7 N 9.8 10^-10 N

6. When a car goes around a circular curve on a horizontal road at constant speed, what force causes it to follow the circular path?

The normal force from the road The friction force from the road The gravitational force The spring force of the car

7. A race car traveling at a constant speed drives around a circular track that is 300 m in diameter with an acceleration of 10 m/s². What is the magnitude of the speed the car is traveling?

0 m/s 39 m/s 15 m/s 55 m/s

8. Two planets have the same surface gravity, but planet B has four times the mass of planet A. If planet A has radius r, what is the radius of planet B?

r/2 r 2r 4r