Since
<span>Vf^2 = 2*a*S </span>
<span>Given S=3.6m, thus </span>
<span>a = Vf^2/(2*3.6) </span>
<span>a = Vf^2/7.2 </span>
<span>Let d be the distance along the slope at which the velocity is 0.5Vf, then </span>
<span>(0.5Vf)^2 = 2*a*d </span>
<span>or </span>
<span>d = (0.5*Vf)^2/(2*a) </span>
<span>with a = Vf^2/7.2, we have </span>
<span>d = 0.9 m</span>
If an object is consist of a negative acceleration or
composed of it, it is likely engaging of having to accelerate in a certain
direction in which the direction is heading towards the opposite of the
direction that is stated and that is likely to be a positive direction.
We know, Impulse of a body is change in momentum.
Also, the final velocity of wood block is 0 m/s.
So, Impulse = Final Momentum - Initial Momentum
Impulse = 0 - ( 0.05 kg × 350 m/s )
Impulse = - 17.5 kg m/s
Therefore, the impulse exerted by the wood on the bullet is -17.5 kg m/s .
The question is poorly written.
ALL of the choices cause a change in something.
A). Force causes a change in velocity.
B). and C). Power and energy cause changes requiring work.
D). Impulse causes a change in momentum.
