Friction is a force that oppose other forces and can slow them down
Answer: temperature of the hot reservoir is 303.52K
Explanation:
Th=temperagture of hot reservoir
Tc=temperature of cold reservoir 263K
Eff=efficiency of the refrigerator
Cop=coefficient of performance
7
Eff=1/cop
Eff=1/7
Eff=0.142
Eff=1-263/th
0.142-1=-263/th
-0.858=-263/th
Th=303.52K
GPE = mgh (for objects close to earth where g can be considered to be constant) Where m is the mass, g is the acceleration due to gravity (which the question has told us to assume is 10ms^-2), and h is the height of the object.
Substituting the values in:
GPE = 70*10*10 = 7000J
Some ice has more salt then the other causing it to float up
