Question

A rock is shot out of a cannon set at an angle of 45° from the ground. The initial velocity of the rock is 15m/s. Where will the rock hit the ground?

Answer 1

Step-by-step explanation:

First, find the time it takes the rock to fall. In the y direction:

s = 0 m

u = 15 sin 45° m/s = 10.6 m/s

a = -9.8 m/s²

Find: t

s = ut + ½ at²

0 = (10.6) t + ½ (-9.8) t²

t = 2.16 s

Next, find the distance traveled in that time. In the x direction:

u = 15 cos 45° = 10.6 m/s

a = 0 m/s²

t = 2.16 s

Find: s

s = ut + ½ at²

s = (10.6) (2.16) + ½ (0) (2.16)²

s = 23.0 m

The rock hits the ground 23 meters from the cannon.