Question

Three forces of magnitude 6N,2N,3N act on a small object in directions north,south and west respectively. Find the direction and magnitude of the resultant force.If the force to move and its mass is 0.2kg.Calculate the initial acceleration.

Answer 1

Given:

$F_1=\rm 6\: N$

$F_2=\rm 2\: N$

$F_3=\rm 3\: N$

The net force

$$F=\sqrt{(F_1-F_2)^2+F_3^2}\\ =\sqrt{(6-2)^2+3^2}=5\:\rm N$$

The direction

$$\theta=\tan^{-1}\frac{4}{3}=53^\circ\; \rm N\; of\; W$$

The acceleration

$$a=\frac{F}{m}=\frac{5\:\rm N}{0.2\:\rm kg}=25\:\rm m/s^2$$