JEE Mains · Physics · STD 11 - 5. work,energy,power and collision
In the given figure, the block of mass \(m\) is dropped from the point ' \(A\) '. The expression for kinetic energy of block when it reaches point ' \(B\) ' is ................
- A \(\frac{1}{2} m g y_{0}^{2}\)
- B \(\frac{1}{2} mgy ^{2}\)
- C \(mg \left( y - y _{0}\right)\)
- D \(mgy _{0}\)
Answer & Solution
Correct Answer
(D) \(mgy _{0}\)
Step-by-step Solution
Detailed explanation
Work done by gravity \(= K _{ B }- K _{ A }\) \(mgy _{0}= K _{ B }-0\) \(K _{ B }= mgy _{0}\)
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