Effects of Forces

Forces have several effects on objects. These effects include: - 

(i)                  Stretching and Restoring force

(ii)                Torsion force

(iii)              Attraction force

(iv)              Friction force

(v)                Compression force

(vi)              Viscosity

(vii)            Repulsion force

(viii)          Air Resistance 

 

Stretching and Restoring

Stretching force is the force produce elongation of object if pulled. For Example, when spring is pulled the stretching force elongate the spring

 

Restoring force

restoring force is the force which cause a body to return to their original shape and size applied force is removed.

 

Compression force

Compressional force is the force which when applied to an object results in decreasing in its volume.

Example when you compress the spring 

 

Attractive force 

Is the force that pulls objects toward each other.

For example, A Magnet always attracts other objects like iron. 

Repulsive force 

Is the force that pushes objects against each other.

 
For example, when the same poles of magnets are closer to each other, they repel 

The figures below show an example of attractive and repulsive force

Torsional Force 

Is a force produced when a solid matter is twisted.

Viscous force

Viscosity is the resistance of a fluid to flow.

For example, water has a lower viscous force than cooking oil, since it has less resistance to flow 

Air Resistance 

Is the force that resists the movement of an object through the air.

Example of this force is viscosity 

 

Factors affecting Air Resistance  

(i)      Size and shape of the body 

(ii)    The speed of fluid 

(iii)  The density of the fluid 

 

Frictional force  

Is the force that prevents a body from sliding. 

For example, an exercise book cannot slide on top of a table due to friction exists between exercise book and table

 

Importance of Friction Force

(i)      Friction between feet and the ground enable man to walk

(ii)    Friction between object on the surface enable it to rest

(iii)  Friction between match and match stick produce heat

(iv)  Friction enable stopper to close the bottle of wine, juice etc.

 

Disadvantage of Friction

(i)      Cause Heat and lead to heat energy which cause the efficiency of machine to be less than 100%

(ii)    Cause wear and tear of various bodies Example, shoes etc.

(iii)  Cause accident due to wearing of our skin when we slide in rough surface

 

Ways of reducing friction

The fraction can be reduced by

(i)      Using lubricant e.g. oil, grease etc.

Lubricant is a liquid like oil placed between machine parts to prevent body to body contact

(ii)    Rollers

(iii)  Polishing

(iv)  Watering  

Normal Force 

Is the force that acts in equal and opposite direction to the weight of a body 

 

Applied Force 

Is the external force that causes the system or body to change position.