If it takes 15 minutes to dry your hair with a 1.200 kw hair drier, how much energy is used in drying your hair?
a. 0.300 kwh
b. 1.200 kwh
c. 1.800 kwh
d. 18.000 kwh

Option (A) is the correct answer.

Explanation:

The given data is as follows.

     Power = 1.200 kW,         Time = 15 minutes = = 0.25 hour

     Energy = ?

Thus, calculate the energy by using the formula as follows.

               Power =

               Energy = Power × Time

                            = 1.200 kW × 0.25 hr

                            = 0.300 kWh

Thus, we can conclude that 0.300 kWh energy is used in drying your hair.

the box does not move because you need to use a force greater than 300 n. you are only using 50 n. it needs to at least be 301 n for the box to move because then it is an unbalanced force and it will move the way that the greater force is pushing it. if you use only 300 n it will be a balanced force and will not move because the force you are exerting on the   box is the same as its force.

hope this !

im sorry if i went too in depth, i am going to include a link to a video on khan academy that will explain this.   hope that you like the video and that it explains more in detail to you.

that is the link.