Centre of mass - 3.2.6

Question 1

Define centre of mass

Answer 1

where whole mass of an object can be thought of as acting at a single point

Question 2

What will happen if a force acts directly on the object through its centre of mass

Answer 2

The object will move in a straight line with either an acceleration or constant velocity

Question 3

What will happen if force does not act directly on the object through centre of mass. ie, sideways

And why

Answer 3

Object will move with an additional rotational motion, due to the turning effect.

Question 4

Why is it easier to get centre of mass for a regular object

Answer 4

Because distribution of mass is equal around this point

Question 5

What is centre of gravity

Answer 5

Point where the entire weight of an objects appaears to act

Question 6

Difference between centre of gravity and centre of mass

Answer 6

gravity = weight
mass = mass

Question 7

How to carry out an experiment for centre of mass

Answer 7

1. get a retort stand, cork and pin and attach to stand, plumb line of string with a small weight
2. Make 2 suspension points in the object/paper
3. Hang 1 suspension point onto the pin on cork.
4. Mark 2 points where plumb line string and paper intersect
5. Join the 2 points
6. Repeat for other suspension point
7. The point of intersection of both lines is centre of mass