energy associate with position or shape
Answer:
The answer to your question is: 13.2 m/s
Explanation:
final speed (fs) = 77 m/s
t = 6.5 s
gravity (g) = 9.81 m/s2
initial speed (is) = ?
Formula
fs = is + gt from this equation we clear "is" = fs - gt
Substitution is = 77 - (9,81)(6.5)
Process is = 77 - 63.8
is = 13.2 m/s
If the pulling is done parallel to the floor with constant velocity, then the box is in equilibrium. In particular, the weight and normal force cancel, so that
<em>n</em> = 38 N
The friction force is proportional to the normal force by a factor of 0.27, so that
<em>f</em> = 0.27 (38 N) ≈ 10.3 N
and so the answer is D.