Using Physics To Make Things Work

Question 0

Where is the centre of mass when an object is freely suspended?

Answer 0

If freely suspended, an object will come to rest with its centre of mass directly below the point of suspension.

Question 1

What is centre of mass?

Answer 1

The centre of mass of an object is that point at which the mass of the object may be thought to be concentrated.

Question 2

The centre of mass of a symmetrical object is along the ____ __ ________.

Answer 2

The centre of mass of a symmetrical object is along the AXIS OF SYMMETRY.

Question 3

What is the equation for time period of a simple pendulum?

Answer 3

T=1/f

Question 4

The time period of a pendulum depends in what?

Answer 4

The length of the pendulum

Question 5

What is a moment?

Answer 5

The turning effect of a force

Question 6

What is the equation for a moment?

Answer 6

M = F x d

Question 7

If an object is not turning, the total clockwise moment must be _______ ________ by the total anticlockwise moment about any _____.

Answer 7

If an object is not turning, the total clockwise moment must be EXACTLY BALANCED by the total anticlockwise moment about any PIVOT.

Question 8

What will happen if the line of action of the weight of an object lies outside the base of the object?

Answer 8

There will be a resultant moment and the object will tend to topple

Question 9

What property of a liquid makes it good for hydraulic systems?

Answer 9

Liquids are virtually incompressible

Question 10

Pressure in a liquid is what?

Answer 10

Transmitted equally in all directions

Question 11

The use of different _____-_________ areas on the effort and ____ side if a hydraulic system enables the system to be used as a _____ __________.

Answer 11

The use of different CROSS-SECTIONAL areas on the effort and LOAD side if a hydraulic system enables the system to be used as a FORCE MULTIPLIER.

Question 12

What is the equation for pressure in the different parts of a hydraulic system?

Answer 12

P=F/A

Question 13

How does an object accelerate when it moves in a circle?

Answer 13

When an object moves in a circle it continuously accelerates towards the centre of the circle.

This acceleration changes the direction of motion of the object, not its speed.

Question 14

What is centripetal force?

Answer 14

The resultant force causing the acceleration when an object moves in a circle. Centripetal force is always directed towards the centre of the circle.