Question

A cannonball is shot from the top of a 30

Answer 1

Answer:

C) 19 m/s

Explanation:

The motion of the cannonball is a projectile motion, which consists of 2 independent motions:

- A uniform motion (constant velocity) along the horizontal direction

- A uniformly accelerated motion (constant acceleration) along the vertical direction

As a result, we have the following:

- The horizontal velocity of the cannonball remains constant during the motion, and it is given by

$v_x = u cos \theta$

where

u = 25 m/s is the initial velocity

$\theta=40^{\circ}$ is the angle

Substituting,

$v_x = (25)(cos 40^{\circ})=19 m/s$

- The vertical velocity keeps changing during the motion due to the acceleration of gravity. However, at the top of the trajectory, the vertical velocity is zero:

$v_y = 0$

This means that at the top of its path, the cannonball has only horizontal velocity, so its velocity is

C) 19 m/s