Q.
A block of mass $\sqrt{3}$ kg rests on a horizontal frictionless $XY$ plane. What would be the acceleration of the block if it is subjected to two forces as shown in figure?
A) 2.5 $ms^{- 2}$
B) 5 $ms^{- 2}$ along $Y$-axis
C) 10$\ ms^{- 2}$ along $X$-axis
D) $15\ ms^{- 2}$ along $Y$-axis
Explanation
(b) Horizontal component of 10N is 10 $\cos{60{^\circ}}$ $ie\ 10 \times \frac{1}{2}$ N or
5 N. It is balanced by 5 N force along $x$-axis
$Y$-component of 10 N force is 10 sin 60 N
$ie,\ 10 \times \frac{\sqrt{3}}{2}\ $N or$\ 5\sqrt{3}\ $N
$a_{y} = \frac{5\sqrt{3}N}{\sqrt{3}\ kg} = 5\ ms^{- 2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.