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Flashcards in P3.2 Deck (32):
1

What is an object with a wide base and low centre of mass more stable than

Objects with a narrow base and a high centre of mass

2

What does not exist in its own right

Centripetal force

3

What is centripetal force always provided by

Something else such as gravitational force, friction or tension

4

What is the centre of mass of an object

The point at which mass the mass of the object may be thought to be concentrated

5

How do u find the centre of mass of a thin, irregular sheet of a material

Make a hole in one end

Put the card through a plum line

Suspend the card

Draw a line where the string goes across the card

Repeat this process and where both lines meet that is the centre of mass

6

What happens if u freely suspend an object

The object will come to rest with its centre of mass directly below the point of suspension

7

Where is the centre of mass of a symmetrical object

Along the axis of symmetry

8

What does the time period of a simple pendulum depend on

On the length of a pendulum

9

What is a moment

The turning effect of a force

10

What happens if an object is not turning

The total clockwise moment must be exactly balanced by the total anti-clockwise moment about any pivot

11

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

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

12

What are virtually incompressible

Liquids

13

Why are liquids virtually incompressible

Because a force exerted or pressure at one point on a liquid will be transmitted to other points in the liquid

14

What enables a hydraulic system to be used as a force multiplier

The use of different cross-sectional areas on the effort and load side of a hydraulic system

15

What happens when an object moves in a circle

It continuously accelerates towards the centre of the circle and this acceleration changed the direction of motion of the body not its speed

16

What is the centripetal force of an object

The result force causing the acceleration in a object moving in a circle

17

What direction in a centripetal force

Towards the centre of the circle

18

The centripetal force needed to make an object perform circular motion increases as......

The mass of the object increases

The speed of the object increases

The radius of the circle decreases

19

Why do hydraulics work

Because liquids are incompressible

20

What is the hydraulic brake

An arrangement of braking mechanism which uses brake fluid

21

What is the time period inversely proportional to

The frequency

22

What is a full in a pendulum

One swing

23

3 examples of pendulums

Rocking chair
Newtons cradle
Swing

24

What has the same pressure in a hydraulic system

The master piston and the slave piston

25

In a hydraulic system what is the work done equal to in a master piston

The slave piston

26

Equation for work done in a piston

Force x the distance moved by the piston

27

What has the same pressure in a hydraulic system

The master piston and the slave piston

28

In a hydraulic system what is the work done equal to in a master piston

The slave piston

29

Equation for work done in a piston

Force x the distance moved by the piston

30

What has the same pressure in a hydraulic system

The master piston and the slave piston

31

In a hydraulic system what is the work done equal to in a master piston

The slave piston

32

Equation for work done in a piston

Force x the distance moved by the piston