Forces And Hookes Law Flashcards
What is a force?
A force is defined as a push or a pull.
What three things can a force do?
Make an object speed up- accelerate
Make an object slow down- decelerate
Change an objects direction.
What are the four common types of forces?
Weight
Air resistance
Friction
Up thrust
What does weight do?
Weight pulls things downwards and acts towards the centre of the Earth.
What does air resistance do?
Air resistance (drag) acts against anything moving through air.
What does friction do?
Friction acts against anything moving.
What does up thrust do?
Keeps things afloat.
What is a force measured in?
A forces measured in neutrons using a neutron meter.
What is mass?
Mass is a measure of the amount of substance in an object.
Mass is measured in kilograms (kg) or grams (g).
Mass is measured using balance or scales.
Your mass is the same on the earth as it would be on the Moon.
What does mass depend on?
Mass depends on the size of the atoms that make up a substance and the way the atoms are packed together.
What is weight?
The weight of an object is the force of gravity acting on it.
The weight of an object is the same as the force you would need to lift it up vertically.
Weight is a force, so it’s measured in neutons.
Gravity changes throughout the universe and so weight changes.
What is the link between mass and weight?
10N=1 kilo.
E.g. 100g = 0.1kg= 1N
What is the equation for weight?
Weight=mass x gravity
What is the value of gravity on the moon?
1.6
What does Hooke’s law state?
Hooke’s Law states that the extension of a spring is directly proportioned to the force applied provided the elastic limit is not exceeded.
What is the elastic limit?
The elastic limit is the point beyond which the spring will not return to its original size and shape when the force is removed I.e it no longer obeys Hooke’s law.
What is the elastic region?
The region which obeys Hooke’s law.
What is the plastic region?
The region beyond the elastic limit.
What is used in science to show the size and direction of a force?
Arrows
If an object is moving at a constant speed, what can be said about the forces acting on it?
They are balanced.
What is the name of the force that opposes motion?
Friction
Describe 2 ways in which we can reduce friction?
Smooth surfaces and lubricant
What do we call the frictional force of air?
Air resistance.
What would happen to a moving object in space?
It would keep on moving.
