Question

State whether the given statement is true or false.
Gravity and friction are both contact forces.
A. True.
B. False.

Answer 1

Hint: Contact force is achieved by touching near-by objects (or) in between any two objects. Non-contact force is achieved by force between two objects by distance from them. Non -contact forces operate at a distance. Contact forces are transferred when things “touch”.

Complete answer:
The force of gravity can be defined as the force earth, moon, or other massively large object attracts another object towards itself. All objects upon earth experience a force of gravity that is directed "downward" towards the centre of the earth.
The friction force is that force exerted by a surface when an object moves across it or a force makes the object move across it. Sliding and static friction are two types of friction forces. It is not always true that the friction force often opposes the motion of an object.
Hence we can clearly say that gravity is a non-contact force and friction is a contact force.
So the above given statement is false. Because friction is a contact force as it acts only during contact with surfaces.

So, the correct answer is “Option B”.

Note:
Non-contact forces operate at a distance - like gravity, two magnets attracting/repelling, or two charged balloons repelling. The distance over which the force operates is readily observable. Contact forces are transferred when things “touch”. Unfortunately- things never really do touch. If we push something, the electrons in the molecules in our skin get close to the electrons in the object we are pushing. These electrons repel each other. We think we are touching the object - it is really a non-contact force operating over a short distance that we cannot readily observe. The difference is nil because the two are really the same- there are no contact forces.