The answer is C, a peer group.
Answer:
Compression in the spring, x = 3.7 cm
Explanation:
It is given that,
Mass of the book, m = 1.6 kg
It can be assumed the spring constant of the spring is, k = 840 N/m
As the book moves down, the change in potential energy of the book is converted to spring potential energy of compression. The mathematical expression is as follows :
x = 0.037 meters
or
x = 3.7 cm
So, the spring is compressed to a distance of 3.7 cm. Hence, this is the required solution.
<span>The maximum possible efficiency, i.e the efficiency of a Carnot engine , is give by the ratio of the absolute temperatures of hot and cold reservoir.
η_max = 1 - (T_c/T_h)
For this engine:
η_max = 1 - [ (20 +273)K/(600 + 273)K ] = 0.66 = 66%
The actual efficiency of the engine is 30%, i.e.
η = 0.3 ∙ 0.664 = 0.20 = 20 %
On the other hand thermal efficiency is defined as the ratio of work done to the amount of heat absorbed from hot reservoir:
η = W/Q_h
So the heat required from hot reservoir is:
Q_h = W/η = 1000J / 0.20 = 5000J</span>
Answer:
I think A golf ball shot out of a small cannon
Explanation:
The car is accelerating at 3 m/s² in the positive direction (to the right). By Newton's second law, the net force on the car in this direction is
∑ F = F[a] - F[f] - F[air] = ma
3100 N - 200 N - F[air] = (650 kg) (3 m/s²)
Solve for F[air] :
F[air] = 3100 N - 200 N - (650 kg) (3 m/s²)
F[air] = 3100 N - 200 N - 1950 N
F[air] = 950 N
