Forces

What do Forces produce on a object

Change in Shape and size

What happens if no resultant force acts on a object

The object moves at a constant speed or is in rest

How does resultant force change velocity of an object

By changing the direction of motion or speed

Spring Constant

F=k/x

Limit of Proportionality

The point on the graph till the Force is proportional to extension

Force perpendicular to motion

• Speed increases if Force increases (Radius and mass constant)

• Radius decreases if force increases (Speed and Mass constant)

• If mass increases, force needs to increase to keep speed and radius constant

Solid Friction

When two surfaces are in contact and it slows down motion and produces heating

Moment

Turning effect of a force (Force x Perpendicular distance)

Principle of Moments

Anticlockwise moment = Clockwise moment

Centre of Gravity

The point on a object where all the weight acts

Expirement to measure Centre of Gravity

1. Hang up a a lamina and suspend a plumb line

2. Mark the position of the plumb line

3. Repeat with different plumb lines from different Positions

4. The point where it intersects is the center of gravity

Different Points

If Centre of mass is below suspension it will be stable

If Centre of mass is above suspension it will topple

If line of action of an object moves outside its base it will fall