Ablock sliding across a level surface has a mass of 2.5 kg and a mechanical energy of 20 joules. what is its velocity?

Hi!

The energy of the block is 4 m/s

To calculate this, you need to use the equation for kinetic energy. The block is sliding (i.e. it's moving). If the object is sliding across a level surface, the only energy it has is kinetic energy, because there is no change in potential energy (which changes with height). So, the mechanical energy will be pure kinetic energy. The equation is the following, derived from the expression for kinetic energy:



Have a nice day!

Magma  is composed of molten rock and is  stored  in the earth's crust. lava is  magma  that reaches the surface of our planet through a volcano vent.