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Flashcards in Chapter 4 Deck (13):
1

What is a MOMENT?

A moment is the turning effect of a force.

2

What is a PIVOT?

A pivot is the point that does not move by rotation.

3

Finish:

When an object is in ___ , the sum of the _____ is ____ to the sum of the _________

When an object is in balance, the sum of the clockwise moments is equal to the sum of the anticlockwise moments.

4

What is the equation for a MOMENT?

Moment = Force × Distance (Perpendicular distance from the pivot)

5

What is MASS?

Mass is the amount of matter in an object.

Mass is constant.

6

What is WEIGHT?

Weight is the downward force on an object due to gravity.

Weight vaires with acceleration due to gravity (g).

7

What is meant by THE CENTRE OF MASS?

The point through which any externally applied force produces straight-line motion but no rotation.

8

What is meant by THE CENTRE OF GRAVITY?

The point through which an object’s weight appears to act.

9

What is the equation for PRESSURE and what is its UNIT?

Presser = Force ÷ Area

P = F ÷ A

Pressure is measured in Nm² or Pa

10

What is the equation for DENSITY?

Density = Mass ÷ Volume

ρ = m ÷ V

ρ = kgms-³ (kgms to the -3)

11

What is UPTHRUST?

The upthrust is the difference between the upper surface force and the lower surface force

12

What is the equation for UPTHRUST?

(h+x)ρAg - ρhAg =xρAg

13

State ARCHIMEDE'S PRINCIPLE

The upthrust exerted on a body immersed in a fluid, whether fully or partially submerged, is equal to the weight of the fluid that the object displaces.