A single movable pulley is used to lift load of 4000N to the height of 50cm .If the efficiency of the pulley system is 75%, calculate the effort distance, effort applied, input work, output work and loss of energy in the simple machine.

What are similarities and differences between refraction, reflection, diffraction and absorption?

You throw a small rock straight up from the edge of a highway bridge that crosses a river. the rock passes you on its way down, 7.00 s after it was thrown. what is the speed of the rock just before it reaches the water 28.0 m below the point where the rock left your hand? ignore air resistance.

Photons with the highest energy have the longest period