JEE Mains · Physics · STD 11 - 5. work,energy,power and collision
A body of mass 2 kg is moving along x -direction such that its displacement as function of time is given by \(x ( t )=\alpha t ^2+\beta t +\gamma m\), where \(\alpha=1 m / s ^2\), \(\beta=1 m / s\) and \(\gamma=1 m\). The work done on the body during the time interval \(t =2 s\) to \(t =3 s\), is _________ J.
- A 49
- B 42
- C 24
- D 12
Answer & Solution
Correct Answer
(C) 24
Step-by-step Solution
Detailed explanation
\( x(t)=t^{2}+t+1 \) \( v(t)=2t+1 \) \( a(t)=2 \) \( F=4N. \) \( Displacement=x(3)-x(2)\) \(=13-7=6m \) \( W=F.S=4\times6=24J \)
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