P8: Forces In Balance

Question 1

What is a vector quantity?

Answer 1

A quantity with SIZE and DIRECTION

Question 2

What is a scalar quantity?

Answer 2

A quantity with SIZE but NO direction

Question 3

What is distance?

Answer 3

The distance travelled in total

Question 4

What is displacement?

Answer 4

The distance between where something started moving and where it stopped

Question 5

What are some examples of vector quantities?

Answer 5

Velocity, force, acceleration, weight, displacement

Question 6

What are some examples of scalar quantities?

Answer 6

Mass, energy, speed, time, distance, power

Question 7

What is a force in physics?

Answer 7

A push or a pull that acts on an object, measured in Newtons (N)

Question 8

If you apply a force to an object, what different things can happen?

Answer 8

It can change shape (squeeze or stretch), can change direction, can change speed

Question 9

What is the difference between a contact and non-contact force?

Answer 9

A contact force is when there is physical touch in order for the force to happen

Question 10

What are some examples of contact forces?

Answer 10

Tension
Air resistance
Friction
Thrust

Question 11

What are some examples of non-contact forces?

Answer 11

Electrostatic
Magnetic
Gravitational
Nuclear

Question 12

What is newtons third law of motion?

Answer 12

When two objects interact with eachother they exert Equal and Opposite forces on eachother

Question 13

What is a resultant force?

Answer 13

A single force that describes all of the forces that are operating on an object

Question 14

What is a balanced force?

Answer 14

When two forces are the same size and in an opposite direction

Question 15

What is an unbalanced force?

Answer 15

When one of the two forces in opposite directions is larger than the other

Question 16

What is a moment?

Answer 16

Turning force around a fixed pivot

Question 17

What is a moment equal too?

Answer 17

Force X distance

Question 18

What are force multiplyers?

Answer 18

Force multiplyers multiply the applied force, allowing you to lift more for less work

Question 19

What is the centre of mass?

Answer 19

The point of an object where its mass can be thought of as being the most concentrated

Question 20

How do you find the centre of mass on a regularly shaped object?

Answer 20

You draw the lines of symetry and where they all cross is the centre of mass

Question 21

How do you find the centre of mass on an irregular shaped object?

Answer 21

You hang a plumb line from different points on the shape and draw a line where it hangs for each of them, where these lines cross is the centre of mass

Question 22

If an object is equilibrium what can you say about all the forces?

Answer 22

That they are balanced

Question 23

If someone is sat 2m from the pivot of the seesaw and is applying a 300N force, what is their total force being applied?

Answer 23

2 x 300 =

600N

Question 24

How do you figure out the resultant force of a shape without a right angle?

Answer 24

1) Figure out the scale
2) Draw in the 2 lines you have been given at the right angles and to scale
3) Measure out the lenghts and angles of those lines to draw them again to make a pallelogram
4) Draw a line from the starting point to the point opposite from it, and meassure the angle and size of that resultant force