JEE Mains · Physics · STD 11 - 5. work,energy,power and collision
A spherical body of mass \(2\,kg\) starting from rest acquires a kinetic energy of \(10000\,J\) at the end of \(5^{\text {th }}\) second. The force acted on the body is \(.....N\)
- A \(40\)
- B \(41\)
- C \(42\)
- D \(43\)
Answer & Solution
Correct Answer
(A) \(40\)
Step-by-step Solution
Detailed explanation
\(\frac{1}{2} \times 2 \times v ^2=10000\) \(\Rightarrow v ^2=10000\) \(\Rightarrow v =100\,m /s\) \(\Rightarrow v = at = a \times 5=100\) \(\Rightarrow a =20\,m / s ^2\) \(F = ma =2 \times 20=40\,N\)
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