2. How tall is a flagpole if the sun is at a 53º angle above the horizon and the shadow is 8.0 meters long?

 

3. Three students were arguing about the height of a parking garage. One student suggested that to determine the height of the garage, they simply had to drop tennis balls from the top and time the fall of the tennis balls.

 

 

If the time for the ball to fall was 1.4 seconds, approximately how tall is the parking garage?

4. An arrow is shot from a bow at an angle of 40º from the horizontal at a speed of 24.0 m/s. Ignoring air resistance, what is the arrow’s maximum height above its launch point?

6. An arrow is shot through an apple. If the 0.1 kg arrow changes speed by 10 m/s during the collision (from 30 m/s to 20 m/s) and the apple goes from rest to a speed of 2 m/s during the collision, then the mass of the apple must be

7. A car has the velocity versus time curve shown.

 

 

Which of the following statements regarding its motion is INCORRECT?

9. A deliveryman moves 10 cartons from the sidewalk, along a 10-meter ramp to a loading dock, which is 1.5 meters above the sidewalk.

 

 

If each carton has a mass of 25 kg, what is the total work done by the deliveryman on the cartons to move them to the loading dock?

14. A book leans against a crate on a table. Neither is moving.

 

 

Which of the following statements concerning this situation is CORRECT?

15. A crate of toys remains at rest on a sleigh as the sleigh is pulled up a hill with an increasing speed. The crate is not fastened down to the sleigh. What force is responsible for the crate’s increase in speed up the hill?

 

 

What is the total impulse delivered by the force (units in kg m/s).

18. A cart is initially moving at 0.5 m/s along a track. The cart comes to rest after traveling 1 m. The experiment is repeated on the same track, but now the cart is initially moving at 1 m/s. How far does the cart travel before coming to rest?

19. A 60.0-kg ball of clay is tossed vertically in the air with an initial speed of 4.60 m/s. Ignoring air resistance, what is the change in its potential energy when it reaches its highest point?

20. A boy jumps from rest straight upward from a flat, stationary concrete surface. The boy, of mass M, leaves the concrete surface with speed v and his center of mass rises a distance d to the highest point of the motion. How much physical work did the average normal force of contact (N) between the boy’s feet and the concrete do on the boy?

22. During an interval of time, a tennis ball is moved so that the angle between the velocity and the acceleration of the ball is kept at a constant 120º. Which statement is true about the tennis ball during this interval of time?

23. An object m, on the end of a string, moves in a circle on a horizontal frictionless table as shown.

 

 

As the string is pulled very slowly through a small hole in the table, which of the following is correct for an observer measuring from the hole in the table?

24. A person tries to balance vertically each of three long uniform cylinders with equal radii on the end of his finger:

 

 

Which object is the easiest to balance and why?