Q. A block of mass $50\ kg$ can slide on a rough horizontal surface. The coefficient of friction between the block and the surface is 0.6. The least force of pull acting at an angle of $30{^\circ}$ to the upward drawn vertical which causes the block to just slide is
A) $29.43\ N$
B) $219.6\ N$
C) $21.96\ N$
D) 294.3 N
Explanation
(d) For limiting condition $f = \mu R$
$F\sin{30{^\circ}} = \mu(mg - F\cos{\ 30{^\circ}})$,
By solving, $F = 294.3\ N$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.