Answer:
v = 54.2 m / s
Explanation:
Let's use energy conservation for this problem.
Starting point Higher
Em₀ = U = m g h
Final point. Lower
= K = ½ m v²
Em₀ = Em_{f}
m g h = ½ m v²
v² = 2gh
v = √ 2gh
Let's calculate
v = √ (2 9.8 150)
v = 54.2 m / s
Answer:
B. 2 meters.
Explanation:
To rotate the capstan a certain amount of torque is required, and if each sailor applies a force at a distance
from the center, then for two sailors the total torque will be
;
therefore, for one sailor to apply the same torque it must be that the torque he applies must be equal to the torque that the two sailors applied:
which gives
.
and since ,
which is choice B.
Answer:
The final kinetic energy of the two-car system is 60,000 J.
Explanation:
Given;
mass of the car, m = 1200 kg
time of motion, t = 8.8 s
final velocity of the car, v = 10 m/s
Apply the principle of conservation of kinetic energy; the initial kinetic energy is equal final kinetic energy.
Therefore, the final kinetic energy of the two-car system is 60,000 J.