Vf = Vi + at
Vf = 0 + 5.4•28
= 151.2m/s..
not sure if its right
<span><span>Velocity is a vector, and the initial and final ones are in opposite directions.
There must have been acceleration in order to change the direction of motion.</span>
A) No. The initial and final velocities are the same.
This is all wrong, and not the correct choice.
It's "Yes", and the initial and final velocities are NOT the same.
B) Yes. The ball had to slow down in order to change direction.
This is poor, and not the correct choice.
The "Yes" is correct, but the explanation is bad.
Acceleration does NOT require any change in speed.
C) No. Acceleration is the change in velocity. The ball's velocity is constant.
This is all wrong, and not the correct choice.
It's "Yes", there IS acceleration, and the ball's velocity is NOT constant.
D) Yes. Even though the initial and final velocities are the same, there is a change in direction for the ball.
This choice is misleading too.
The "Yes" is correct ... there IS acceleration.
The change in direction is the reason.
The initial and final velocities are NOT the same. Only the speeds are.
</span>
Answer:
Option C.
Impulse = mass × change in velocity
Explanation:
Impulse is defined by the following the following formula:
Impulse = force (F) × time (t)
Impulse = Ft
From Newton's second law of motion,
Force = change in momentum /time
Cross multiply
Force × time = change in momentum
Recall:
Impulse = Force × time
Thus,
Impulse = change in momentum
Recall:
Momentum = mass x velocity
Momentum = mv
Chang in momentum = mass × change in velocity
Change in momentum = mΔv
Thus,
Impulse = change in momentum
Impulse = mass × change in velocity
A
The horizontal force cancels out. The two 4Ns go in opposite directions. So they don't affect the outcome.
The Vertical force is 6N up - 2 N down = 4 N Up
Answer 4 N up
B
The horizontal and vertical forces cancel out. Each gives 3N - 3N =0
The net force is 0
C
You only have horizontal forces on this one
5N - 3N = 2N
The answer is 2N to the right.
