Question

Two forces 3N and 4N act on a body of mass 5 kg at right angles. The acceleration of the body is

• A. $\frac{7}{5}{m/s}^2$
• B. $1{m/s}^2$
• C. $\frac{1}{5}{m/s}^2$
• D. $\frac{5}{7}{m/s}^2$

Answer 1

The correct option is B $1{m/s}^2$

As the forces are acting at an angle ${90}^0$ so the $net$ force will be

$F=\sqrt{F_1^2+F_2^2+2F_1{F}_{2}Cos{90}^0}=\sqrt{9+16+0}=5N$

so the acceleration will be $a=\frac{F}{m}=\frac{5N}{5kg}=1m/s^2$