The displacement of a particle moving under the action of a force $\vec{\mathrm{F}}=2\overset{^}{\mathrm{i}}+\mathrm{b}\overset{^}{\mathrm{j}}+\overset{^}{\mathrm{k}}$ is $\vec{\mathrm{d}}=\overset{^}{\mathrm{i}}+\overset{^}{\mathrm{j}}+\overset{^}{\mathrm{k}}$. Find the value of $b$ if the work done by the force is zero.

(Shift II Memory Based)

Question

The displacement of a particle moving under the action of a force $\vec{\mathrm{F}}=2\overset{^}{\mathrm{i}}+\mathrm{b}\overset{^}{\mathrm{j}}+\overset{^}{\mathrm{k}}$ is $\vec{\mathrm{d}}=\overset{^}{\mathrm{i}}+\overset{^}{\mathrm{j}}+\overset{^}{\mathrm{k}}$. Find the value of $b$ if the work done by the force is zero.

(Shift II Memory Based)

YESPYQ · Accepted Answer

Correct answer: c) -3. $\mathrm{W}=\vec{\mathrm{F}}.\vec{\mathrm{d}}\ 0=\left(\overset{^}{2\mathrm{i}}+\mathrm{b}\overset{^}{\mathrm{j}}+\overset{^}{\mathrm{k}}\right).\left(\overset{^}{\mathrm{i}}+\overset{^}{\mathrm{j}}+\overset{^}{\mathrm{k}}\right)\ 0=2+\mathrm{b}+1\ \mathrm{b}=-3$

The displacement of a particle moving under the action of a force \(\vec{\mathrm{F}}=2\overset{^}{\mathrm{i}}+\mathrm{b}…

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