JEE Mains · Physics · STD 11 - 5. work,energy,power and collision
A block of mass \(10\,kg\) is moving along \(x\)-axis under the action of force \(F=5 x\; N\). The work done by the force in moving the block from \(x =2\,m\) to \(4\,m\) will be ............\(J\).
- A \(30\)
- B \(20\)
- C \(10\)
- D \(50\)
Answer & Solution
Correct Answer
(A) \(30\)
Step-by-step Solution
Detailed explanation
Work done \(=\int Fdx\) \(\int \limits_2^4 5 x d x=5\left[\frac{ x ^2}{2}\right]_2^4\) \(=\frac{5}{2}[16-4]\) \(=30\,J\)
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