P3 - Centre of Mass Flashcards
Describe the centre of mass.
The centre of mass is the point where all the weight of an object appears to act.
What happens to an object which is freely suspended?
A freely suspended object will come to rest with the centre of mass below the point it is suspended from - eg. hanging baskets always return to below the hook.
How do you find the centre of mass of a symmetrical body?
Drawn lines from the axis of symmetry. Where the lines cross is where the centre of mass is.
How do you find the centre of mass for an unsymmetrical or irregular body?
Freely suspend the object from a point using a clamp stand. Then use a plumb line and draw a line down from the suspension point. Suspend the object from another point and draw down another line. Where the two lines cross is the centre of mass.
The centre of mass can be a point where there is no mass such as a tyre or a mug.
What does the time period of a pendulum depend on?
It’s length.
