Malar is playing with a toy car and track set. She has made a hill to let the car roll down, followed by a series of small hills and then a short flat section on the floor. The car starts at the top of the hill which is 137 cm above the short flat section. How much energy was lost due to friction (between the car and the sides of the track, and the car’s axels) during the entire trip? You don’t have any details about the time while the car is going down the hill or through the loop, so you don’t know how fast it is going at the top of the loop. Mass is 150 g

E = 2.01 J

Explanation:

The energy lost by the car due to friction through the entire trip must be equal to the potential energy of the car at the starting point.

Energy Lost = E = Potential Energy

E = mgh

where,

m = mass of car = 150 g = 0.15 kg

g = acceleration due to gravity = 9.81 m/s²

h = height of the track = 137 cm = 1.37 m

Therefore,

E = (0.15 kg)(9.81 m/s²)(1.37 m)

E = 2.01 J

electrical power

weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards