P8

Question 1

What is Displacement?

Answer 1

Distance in a given direction

Question 2

What is a vector quantity?

Answer 2

Physical quantity which has magnitude and direction

Question 3

What is a scalar quantity?

Answer 3

A quantity with only magnitude

Question 4

How can a vector quantity be represented?

Answer 4

By an arrow in the direction of the vector, and of length in proportion to the magnitude.

Question 5

What can forces do to an object?

Answer 5

Change its shape or change its motion or state of rest

Question 6

What is the unit of force?

Answer 6

Newton

Question 7

What is a contact force?

Answer 7

A force that acts on objects when the objects touch eachother

Question 8

Describe the force that is created when 2 objects interact.

Answer 8

Equal and opposite

Question 9

What is the resultant force of 2 objects acting on each other?

Answer 9

A single force that has the same effect as all the forces acting on an object.

Question 10

What happens to an object if the resultant force of an object is 0?

Answer 10

The object stays at rest or maintains its speed

Question 11

What happens to an object if its resultant force is greater than 0?

Answer 11

The speed or direction of the object will change.

Question 12

What does a free body force diagram of an object show?

Answer 12

The forces acting on it

Question 13

What is the moment of a force?

Answer 13

A measure of the turning effect of the force on an object

Question 14

What is the equation for the moment of a force around a pivot?

Answer 14

moment(M)=force(F) X Perpendicular distance from the line of action of the force to the pivot(d)

Question 15

What are the units for the moment equation?

Answer 15

Newton meters(Nm)= Newtons(N) X Meters(m)

Question 16

What can be used to exert a force that is greater than the effort?

Answer 16

A lever

Question 17

What does a lever act as?

Answer 17

A force multiplier

Question 18

How are gears used?

Answer 18

To change the moment of a turning effect

Question 19

What happens to increase the moment of a turning effect?

Answer 19

a small gear wheel needs to drive a larger gear wheel

Question 20

What is the centre of mass of an object?

Answer 20

The point where it’s mass can be thought of as being concentrated.

Question 21

What happens when an object is freely suspended?

Answer 21

It comes to rest with its centre of mass directly underneath the point of suspension

Question 22

Where is the centre of mass of a symmetrical object?

Answer 22

Along the axis of symmetry

Question 23

What does w1d1=?

Answer 23

w1d1=w2d2

Question 24

If an object at rest doesn’t turn, what does the sun of the anti-clockwise moment at any point equal?

Answer 24

the sun of the clockwise moments about that point.

Question 25

What happens to an object when a force acting in an object doesn’t pass through a fixed point?

Answer 25

The object can turn around that point

Question 26

What determines whether the moment acts clockwise or anticlockwise?

Answer 26

The direction of the force and position of the fixed point

Question 27

The parallelogram of forces is what?

Answer 27

Scale diagram of 2 force vectors

Question 28

What is the parallelogram of forces used for?

Answer 28

to find the resultant of 2 forces that do not act along the same line

Question 29

What does resolving a force mean?

Answer 29

Finding perpendicular components that have a resultant force that is equal to the force

Question 30

How do u resolve a force in 2 perpendicular directions?

Answer 30

Draw a rectangle with adjacent sides along the 2 directions so that the diagonal represents the force vector.