Question

A force of magnitude 50N is required at an angle of 45${}^o$ from the horizontal to pull a 70 kg box across a frictionless horizontal surface. Find out the acceleration of the box ? (sin ${45}^o=cos{45}^o=0.7$)

• A. 0.5 $m/s^2$
• B. 0.7 $m/s^2$
• C. 5 $m/s^2$
• D. 35 $m/s^2$
• E. 50 $m/s^2$

Answer 1

Answer: (A)

0.5 $m/s^2$

Given : $F=50$ N $m=70kg$

Horizontal component of force $F_H=F$ $cos{45}^o=50\times 0.7=35$ N

Thus acceleration of the box $a=\frac{F_H}{m}=\frac{35}{70}=0.5$ $m/s^2$