MCQ
Two persons $A$ and $B$ perform same amount of work in moving a body through a certain distance ${d}$ with application of forces acting at angle $45^{\circ}$ and $60^{\circ}$ with the direction of displacement respectively. The ratio of force applied by person $A$ to the force applied by person $B$ is $\frac{1}{\sqrt{x}}$. The value of $x$ is ...... .
  • $2$
  • B
    $3$
  • C
    $1$
  • D
    $4$

Answer

Correct option: A.
$2$
a
$\text { Given } {W}_{{A}}={W}_{{B}}$

${F}_{{A}} {d} \cos 45^{\circ}={F}_{{B}} {d} \cos 60^{\circ}$

${F}_{A} \times \frac{1}{\sqrt{2}}={F}_{{B}} \times \frac{1}{2}$

$\frac{{F}_{{A}}}{{F}_{{B}}}=\frac{\sqrt{2}}{2}=\frac{1}{\sqrt{2}}$

${x}=2$

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