Answer:
This could represent something like sliding a small rock across an icy lake.
Explanation:
A 20N force of gravity (weight), and 20N normal force exerted back onto the object imply it is on the ground and has no vertical motion. There is a net force of 0N
An 80N force to the left and a 5N force to the right create a net force of 75N to the left. This means that there is a force acting on the object that makes it accelerate to the left. 80N represents a push or pull force and 5N represents a relatively small frictional force due to the object being slid on a surface such as steel or in this case ice.
Answer:
232 J/K
Explanation:
The amount of heat gained by the air = the amount of heat lost by the tea.
q_air = -q_tea
q = -mCΔT
q = -(0.250 kg) (4184 J/kg/ºC) (20.0ºC − 85.0ºC)
q = 68,000 J
The change in entropy is:
dS = dQ/T
Since the room temperature is constant (isothermal):
ΔS = ΔQ/T
Plug in values (remember to use absolute temperature):
ΔS = (68,000 J) / (293 K)
ΔS = 232 J/K
Answer:
Yes , insulation has no role
