Simple machines, such as pulleys, levers, and gears, are never 100 percent efficient. This means that the energy you put into them is always greater than the useful energy you get out of them. Why is this

When many atoms are split in a chain reaction, a large explosion occurs. this is an example of what type of energy conservation

The coefficient of friction is a number that represents the resistance to sliding between two in contact with one another.

Awater balloon launcher uses an elastic band with a spring constant of 115 n/m to use thee launcher you stretch thee band back with a balloon n it the water balloons have a mass of 1.3 kg a) if you stretch the band by 0.8 m, what elastic force will the band exert? b) with the band stretched 0.8 m, how much elastic potential energy is stored in the spring? c) if you release the band, it pushes forward. what is the kinetic energy of the balloon when it reaches the natural length of the band? d) what is the speed of the balloon when it reaches the natural length of the band?