Answer:
The magnitude of the frictional force is 
Explanation:
From the question we are told that
The force exerted on the box is 
Generally for the box to remain at rest then it means that the frictional force is greater than or equal to the force applied to move it i.e

=> 
A scientific theory is an explanation of an aspect of the natural world that can be repeatedly tested and verified in accordance with the scientific method, using accepted protocols of observation, measurement, and evaluation of results. Where possible, theories are tested under controlled conditions in an experiment.
Answer:
1353.38 Watt
Explanation:
T₁ = Initial temperature of the house = 35°C
T₂ = Final temperature of the house = 20°C
Δt = Time taken to cool the house = 38 min = 38×60 = 2280 s
m = mass of air in the house = 800 kg
Cv = Specific heat at constant volume = 0.72 kJ/kgK
Cp = Specific heat at constant pressure = 1.0 kJ/kgK
Heat removed
q = mCvΔT
⇒q = 800×720×(35-20)
⇒q = 8640000 J
Average rate of hear removal


∴ Power drawn by the air conditioner is 1353.38 Watt