1. The force that opposes motion is

Fiction is a force that alerts opposes motion in a direction opposite to motion.

friction

Opposes motion

For a 1 kWh, heat supplied for the cost of furnace is = $1.66 *1 0^-5 /kJ * 3600 =$0.06/kWh.

Therefore, supplied heat for natural gas furnace is $0.06/kWh which is lower than $0.12/kWh cost of electricity of refrigerator.

Explanation:

Solution

Given that:

The thermal efficiency of furnace = 0.8 or 80%

The cop of refrigerant COP = 3.5

The unit cost of electricity for refrigerant is =$ 0.12kWh

The unit cost of natural gas of furnace is = $1.40/therm

1 therm = 105,500 kJ

Now,

In the summer the usage or utilization of lightening in the house will be lesser than winter, hence the total cost of energy used in the household will be decreased.

Thus,

In winter, the utilization of lightening will be higher with regards to electricity

For a natural gas furnace it is given below:

The unit cost =$1.40/ηth (I therm/105,500)

= 1.40/0.8 (I therm/105,500)

= $1.66 *1 0^-5 /kJ

For a 1 kWh, heat supplied for the cost of furnace is = $1.66 *1 0^-5 /kJ * 3600 =$0.06/kWh.

So,for the heat supplied for natural gas furnace is $0.06/kWh which is less er than $0.12/kWh cost of electricity of refrigerator.

Therefore, the efficiency of energy lightning will reduce the total energy cost of the building both in winter and summer.