Forces

Question 1

Vector quantity

Answer 1

Have a magnitude and a direction
lots of physical quantities have a vector quantity
e.g: force, velocity, displacement, acceleration, momentum etc

Question 2

Scalar quantities

Answer 2

ONLY have magnitude and NO direction

e.g speed, distance, time, mass, temperature etc

Question 3

What is it called when 2 objects HAVE to be touching for a force to act?

Answer 3

A contact force

e.g: friction, air resistance etc

Question 4

What is is called when 2 objects DON’T need to touch for the force to act?

Answer 4

A non-contact force

e.g: magnetic force, gravitational force etc

Question 5

What is mass?

Answer 5

It’s the amount of stuff in an object
The object will have the same value anywhere in the universe
Measured kilograms (kg) and measured with a mass balance
MASS IS NOT A FORCE

Question 6

What is weight?

Answer 6

It’s the force acting on an object due to gravity and can change depending on the objects location
Measured in newtons (N) and is measured with a newton-meter

Question 7

What is the calculation that links weight, mass and gravitational field strength?

Answer 7

Weight(J) = Mass (kg) x Gravitational field strength(N/kg)
W= m x g

Question 8

What is the symbol that shows if you increase the mass the weight increases to?

Answer 8

The direct proportionality symbol

W∝m

Question 9

How do you calculate the resultant force?

Answer 9

You take away the bigger force from the smaller one (opposite each other)
Then you get the force and label it the direction the bigger force is going at e.g: 200N to the left

Question 10

How do you convert joules into newton metres?

Answer 10

1 J = 1 Nm

Question 11

How can you find out how much work has been done using an equation?

Answer 11

Work done (J)= Force (N) x distance (m)
W= Fs

Question 12

What happens when a force moves an object through a distance?

Answer 12

Energy is transferred and work is done on an object

Question 13

How do you use scale drawings to find resultant forces?

Answer 13

1. draw a scale drawing of the forces acting
2. Choose a sensible scale (e.g 1cm = 1 N)
3. Draw the resultant from the tail of the first arrow to the tip of the last arrow
4. Measure the length of the resultant with a ruler and use the scale to find the force in N
5. Use a protractor to measure the direction as a bearing

Question 14

If all of the forces acting on an object combine to give a resultant force of zero, what’s it in?

Answer 14

Equilibrium