Question

11. ball is thrown vertically upward with a speed of 30.0 m/s.(a) How high does it rise?

 m

(b) How long does it take to reach its highest point?

 s

(c) How long does the ball take to hit the ground after it reaches its highest point?

 s

(d) What is its velocity when it returns to the level from which it started?

 m/s

Answer 1

Given:

$v_0=30.0\:\rm m/s$

(a)

$$h_{\max}=\frac{v_0^2}{2g}=\frac{30.0^2}{2*9.8}=45.9\:\rm m$$

(b)

$$t=2\frac{v_0}{g}=2*\frac{30.0}{9.8}=6.1\:\rm s$$

(c)

$$t=\frac{6.1}{2}=3.1\: \rm s$$

(d)

$$v=v_0=30.0\:\rm s$$