Gravity holds us to the surface of the Earth and keeps our atmosphere wrapped around our planet. An object’s weight is a measure of the gravitational force acting on it.

GRAVITY

This results in Earth having a gravitational strength of 9.8 m/s² close to the surface (also known as 1 g), which naturally decreases the farther away one is from the surface. In addition, the force of gravity on Earth actually changes depending on where you’re standing on it.

Fundamental force, also called fundamental interaction, in physics, any of the four basic forces—gravitational, electromagnetic, strong, and weak—that govern how objects or particles interact and how certain particles decay.

Characteristics of Force:

• Forces are due to an interaction of at least two objects.
• It may change the state of motion of an object.
• It may change the shape of an object.
• Forces applied on an object in the same direction add to one another and the resultant is in the same direction.

It has two important properties: strength and direction. When two equal forces act in opposite directions the result is that the forces are balanced and there is no motion. The process of moving or changing position. When one force is stronger than the other the result is motion.

Methods for decreasing friction:

• Make the surfaces smoother. Rough surfaces produce more friction and smooth surfaces reduce friction.
• Lubrication is another way to make a surface smoother.
• Make the object more streamlined.
• Reduce the forces acting on the surfaces.
• Reduce the contact between the surfaces.

Friction stops things from sliding apart. If there was no friction everything would slide to the lowest point. It would be impossible to climb up anything. With no friction the only possible movement would be falling to a lower point under gravity.

It opposes motion, meaning if something is sliding on the floor, friction is the force that makes it eventually come to a stop. In a world without friction, the object would continue to slide forever, if not acted on by another force.

Thus friction occurs for every task that involes contact and relative motion of any two surfaces. The only walk that you can perform without friction is a space-walk while every other action that involves contact of two surfaces and motion involves friction.

Frictional forces oppose an object’s motion or intended motion. Depending on the circumstance, this can be good or bad. Without friction, we wouldn’t be able to walk, run, or drive our cars. Without friction, our feet would slide over the ground and motion would look similar to cartoon characters running in place.

Newtons third law says that every action has an equal and opposite reaction………… when you walk you push the ground with your foot backwards….the friction force pushes you forward with the same force……if there was no friction then you will keep on moving your legs on the same spot without going anywhere…

Friction is the force that opposes the tyre rubber from sliding on the road surface. This friction avoids skidding of vehicles. Applications of breaks in the vehicle to stop it- Friction braking is the most widely used braking method in vehicles.

friction can cais the following effects.

• it produces heat.
• it sometimes wore and tore things.
• it help in making balance of anything.