Question

4. A physics student throws two bricks from the top of Fawcett Hall. Brick A is thrown straight up with an initial speed vo, and brick B is thrown straight down with the same initial speed. If air resistance is negligible, when they strike the ground

      a) B has greater speed.      b) A has greater acceleration.      c) B has greater acceleration.

      d) A and B have same speed.      e) A has greater speed.

5. A bullet shot straight up returns to its starting point in 10 s. If it moved frictionlessly, its initial speed must have been _____ m/s.

      a) 24.5       b) 9.8        c) 49         d) 196        e) 98

6. A butterfly moves with a speed of v = 12.0 m/s. The x-component of its velocity is 8.00 m/s. The angle between the direction of its motion and the x-axis must be

      a) 48.2°      b) 41.8°      c) 53.0°      d) 33.7°      e) 30.0°

7. Two displacement vectors have magnitudes of 5 m and 7 m, respectively. When these two vectors are added, the magnitude of the sum is

      a) between 2 m and 12 m.      b) larger than 12 m.      c) 12 m.      d) 2 m.

      e) smaller than 2.

8. A ball thrown horizontally from a point 24 m above the ground, strikes the ground after traveling horizontally a distance of 18 m. Its initial speed was _____ m/s.

      a) 8.13       b) 13.1       c) 39.8       d) 7.35       e) 12.5

9. You hit a tennis ball over the net. When the ball reaches its maximum height, its speed is

      a) greater than its initial speed.      b) less than its initial speed.

      c) equal to its initial speed.      d) zero.

Answer 1

The solution is given below.

Thank you.