Question

A small child tries to move a large rubber toy placed on the ground. The toy does not move but gets deformed under her pushing force $\left(F\right)$ which is obliquely upward as shown. Then

• A. The resultant of the pushing force $\left(F\right)$, weight of the toy, normal force by the ground on the toy and the frictional force is zero
• B. The normal force by the ground is equal and opposite to the weight of the toy
• C. The pushing force $\left(F\right)$ of the child is balanced by the equal and opposite frictional force
• D. The pushing force $\left(F\right)$ of the child is balanced by the total internal force in the toy generated due to deformation

Answer 1

The correct option is A The resultant of the pushing force $\left(F\right)$, weight of the toy, normal force by the ground on the toy and the frictional force is zero

According to newton second law

$F=ma$

So

Since there is no acceleration of body , $a=0$ hence $F=0$ therefore sum of all forces acting on body must be equal to zero. Therefore sum of pushing force, weight of toy and normal reaction by ground and friction by ground must be equal to zero.