Answer:
1) Option D
2) Option D
3) Option C
Explanation:
1) Kinetic energy [tex]=\frac{1}{2} mv^2[/tex]
m = 500 kg
v = 10 m/s
Kinetic energy [tex]=\frac{1}{2} *500*10^2=25000 J[/tex]
Option D is the correct answer.
2) Potential energy = mgh
m = 25 kg
g = 10 m/s²
h = 42 m
Potential energy = 25 * 10 * 42 = 10500 J
Option D is the correct answer.
3) Thermal equilibrium means no heat flow from each other two systems, that is achieved when both systems have same temperature.
Option C is the correct answer.