Answer:

Explanation:
Each time the work done to raise a given mass is

here we know that


now we have


since it is just 25% of actual energy consumed as we know its efficiency is 25%
so we have total energy consumed in this way


now if it took N number of times so burn the fat of a pizza then


Answer:
A
Explanation:
blue stars have a hotter sufarce arra, thats what makes them brighter.
Answer:
B) The car at point C has less kinetic energy than the car at point B.
Explanation:
We have two types of energy involved in this situation:
- Gravitational potential energy: this is the energy related to the heigth of the car, and it is given by
, where m is the mass of the car, g is the gravitational acceleration, and h is the heigth of the car. The potential energy is higher when the car is located higher above the ground.
- Kinetic energy: this is the energy due to the motion of the car, and it is given by
, where m is the mass of the car and v is its speed. The kinetic energy is higher when the speed of the car is higher.
- The law of conservation of energy states that the total mechanical energy of the car (sum of potential energy and kinetic energy:
) is constant). This implies that when the car is at a higher point, the kinetic energy is less (because U is larger, so K must be smaller), while when the car is at a lower point, the kinetic energy is larger.
- Based on what we have written so far, we can conclude that the correct statement is:
B) The car at point C has less kinetic energy than the car at point B.
Because the car at point C is located at a higher point than point B, so the car at point C has larger potential energy than at point B, which implies that car at point C has less kinetic energy than the car at point B.
Answer:
The value is 
Explanation:
From the question we are told that
The mass of the shed is 
The length of the rope is 
The angular speed of the shed is 
Generally the force exerted on the shed is mathematically represented as

=> 
=>
Answer:
it is to do with the static electricity produced by using the comb