Answer:
I think that when a book hits the ground its potential energy converts into kinetic energy and then kinetic energy is transformed into sound and heat energy.
Explanation:
Answer:2.517 J/K
Explanation:
Given
Reservoir 1 Temperature 
Reservoir 2 Temperature 
Let Q is the amount of heat Flows i.e. 
thus change in Entropy is given by 



Answer:
write your question properly
Answer:
56250 N
Explanation:
mass, m = 6000 kg
initial speed, u = 20 m/s
final speed, v = 5 m/s
distance, s = 20 m
Use third equation of motion

5 x 5 = 20 x 20 + 2 a x 20
25 = 400 + 40 a
a = - 9.375 m/s^2
Braking force, F = mass x acceleration
F = 6000 x 9.375
F = 56250 N