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Work Energy Power

JEE Main level, single correct, medium

8 of 183

Question 8 of 183

A force $\overrightarrow{\mathrm{F}}=2 \hat{i}+\mathrm{b} \hat{j}+\hat{k}$ is applied on a particle and it undergoes a displacement $\hat{i}-2 \hat{j}-\hat{k}$ . What will be the value of $b$ , if work done on the particle is zero.

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Answer: (B) $\frac{1}{2}$

\begin{aligned} & w=0 \\ & \therefore \quad \vec{F} \cdot S=0 \\ & (2 \hat{i}+b \hat{j}+\hat{k}) \cdot(\hat{i}-2 \hat{j}-\hat{k})=0 \\ & 2-2 b-1=0 \\ & b=\frac{1}{2}\end{aligned}

JEE Main question paper PDF

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JEE Main 2025 Apr 2 Shift 1 question paper

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More Physics practice

JEE Main Physics practice question on Work Energy Power (Work done), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.

A force F→=2i^+bj^+k^\overrightarrow{\mathrm{F}}=2 \hat{i}+\mathrm{b} \hat{j}+\hat{k}F=2i^+bj^​+k^ is applied on a particle and it undergoes a displacement i^−2j^−k^\hat{i}-2 \hat{j}-\hat{k}i^−2j^​−k^. What will be the value of bbb, if work done on the particle is zero.

JEE Main question paper PDF

More Physics practice

A force $\overrightarrow{\mathrm{F}}=2 \hat{i}+\mathrm{b} \hat{j}+\hat{k}$ is applied on a particle and it undergoes a displacement $\hat{i}-2 \hat{j}-\hat{k}$ . What will be the value of $b$ , if work done on the particle is zero.