Question

Which of the following classes of force is different from others?
a) Magnetic Force
b) Electrical Force
c) Gravitational Force
d) Stretching of a spring

Answer 1

Hint : Force is the root of the motion of a stationary body, preventing, decreasing, or enhancing the speed of a body and variation in the shape or body size. Contact force is described as the force within two bodies when they are in actual contact. Non-contact force is represented as the force within two bodies when they are not in natural touch.

Complete step-by-step solution:
Contact forces are such forces that are applied to objects by immediate contact. The forces which operate on bodies when they are in real contact are named the contact forces. A contact force is described as a force within two objects that are in actual contact. For example, hitting a soccer ball is an example of a contact force since actual contact is between the bottom and the ball.
The following forces come under the category of Contact Forces: - Frictional forces, Tension force as applied through strings, Normal reaction force, the force exerted during a collision, the force applied by a spring, the force applied by a spring, force applied as a pull or push, the force exerted during the collision.
Non-Contact force forces act on bodies without implying touch and are named the non-contact forces. A non-contact force is described as a force within two objects that are not in physical contact. For example, the Earth and the Moon attraction is a non-contact force considering the two never get in contact. A non-contact force is also named a field force.
The following forces come under non-contact forces: Gravitational Force, Electrostatic Force, Magnetic Force.
Stretching of a spring is different from others.
Option (d) is correct.

Note: Non-contact forces permit remote parts of the atmosphere to force an object without staying in contact with it. Thus, a magnet draws or opposes another magnet; a rubbed rubber balloon pulls other charged things; the Earth attracts anything having mass.