MOMENTS

Question 1

What type of quantity are moments

Answer 1

Vector

Question 2

What is the formula

Answer 2

F x D = Nm

Question 3

What is the principal of moments

Answer 3

When a body is in equilibrium, sum of anticlockwise moments = sum of clockwise moments

Question 4

What is the definition of the centre of gravity

Answer 4

A point ,within or outside, of the object through which the entire weight of the object seems to act on.

Question 5

where is the centre of gravity in a regularly shaped object

Answer 5

Geometrical centre of the object

Question 6

how to find the centre of gravity in an irregularly shaped object

Answer 6

LAMINA TEST

Question 7

What are the steps of a lamina test

Answer 7

1. make a small hole near the end of an object using a pin and let it suspend freely from a pin suspended from a cork
2. Suspend a plumbline from the same pin
3. mark the plumbline along the lamina
4. Repeat steps 1-3 with the lamina suspended from different holes made near the edge of the lamina
5. centre of gravity is the intersection point of all the lines drawn

Question 8

How will a stable object react when it is tilted

Answer 8

It will move back to the same position after tilting

Question 9

How will an unstable object react when it is tilted

Answer 9

It will move to a different position after tilting

Question 10

How to increase stability of an object

Answer 10

• Increase the base of the object
• Lower the centre of gravity

Question 11

How does increasing the base of the object increase the stability

Answer 11

object has to tilt more for the weight to act on the pivot

Question 12

How does lowering the centre of gravity increase the stability of an object

Answer 12

• can be done by adding more mass to the base of the object
• The centre of gravity will shift towards the base as more of the mass is at the base
• object will have to tilt more for the weight to act on the pivot