The current flowing in an appliance connected to a 120v source is 2a. how many kilowatt-hours of electrical energy does the appliance use in 4h

0.96 kWh

Explanation:

First of all, we can find the power of the appliance using the formula:

where

V = 120 V is the voltage of the source

I = 2 A is the current

Substituting,

Now we want to find the amount of energy used by the applied in a time of

t = 4 h

The amount of energy is given by

where

P = 0.24 kW

t = 4 g

Substituting,

fgravity=10x10=100n case 1

fgravity=30x20=600n case 2

6 times more