Physics
Answer
We are unable to push a wall or a tree because both are rigid and fixed to the ground. When we apply force, the wall or tree applies an equal and opposite force back on us so that the resultant force becomes zero. Since they are very heavy, firmly attached, and not free to move, our applied force is not enough to change their state of rest, so they remain unmoved.
Related Questions
How is force different from energy?
How do our muscles obtain energy to exert a force?
Name two sports that are played by changing the speed and direction of motion of objects.
Some of the facts that you have learnt till now are listed below. Tick (✓) the facts that are correct and cross (x) the facts that are incorrect.
(a) Force can only change the direction and motion of a body.
(b) The SI unit of force is newton.
(c) The resultant force is the total force acting on a body.
(d) A lot of force can change the mass of a body.
(e) The body only moves if the applied force is sufficient.