I know the formulae,but really dont understand the difference
That is the difference.
Speed the distance travelled in unit time.
KE is the ability to do work.
I'd rather be hit by an object with a lot of speed than one with a lot of energy.
A pea and an express train may be travelling at the same 'speed' but you know which one has more KE. What is the essential difference between to two projectiles?
PS They both have the same Kinetic Energy per gram.
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