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

where
u = 25 m/s is the initial velocity
is the angle
Substituting,

- 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:

This means that at the top of its path, the cannonball has only horizontal velocity, so its velocity is
C) 19 m/s
The answer is the letter ( d )
Answer:
6000 kilometers
Explanation:
multiply the length value by 1000
Answer:Take into account the the Earths gravity is 9.8 meters a second
Explanation:
Gravity pulls down on the ball at g=-9.81 m/s^2. Up is positive, down is negative.The ball started at a certain initial velocity of Vi m/s. Time it took is t=4s. Final velocity is Vf=0 m/s, because at the highest point the ball stops moving.
Vf=(g*t)+Vi
Rearrange for Vi.
Vi=Vf-(g*t)
Vi=0-(-9.81*4)=39.24 m/s (upward)
Think about it this way for the non-mathematical approach. The ball stops at the top. The initial velocity gets reduced by 9.81 m/s every second, and reaches 0 m/s at the top. It took 4 seconds, so 9.81*4 is equal to the initial upward velocity.