JEE Mains · Physics · STD 11 - 5. work,energy,power and collision
A body of mass \(5\,kg\) is moving with a momentum of \(10\,kg\,ms ^{-1}\). Now a force of \(2\,N\) acts on the body in the direction of its motion for \(5\,s\). The increase in the Kinetic energy of the body is \(...........J\).
- A \(30\)
- B \(29\)
- C \(28\)
- D \(27\)
Answer & Solution
Correct Answer
(A) \(30\)
Step-by-step Solution
Detailed explanation
Given \(M =5\,kg\) \(P _{ i }=10\,kg\,m / s \text { (initial momentum) }\) \(\text { Impulse }= F \Delta t =\Delta P = P _{ f }- P _{ i }\) \(2 \times 5= P _{ f }-10\) \(P _{ f }=20\,kg\,m / s \text { (final momentum) }\) \(\text { Increase in } KE = KE _{ f }- KE _{ i }\)…
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