Forces And Waves Flashcards
A force that acts when touching something
Contact Force
E.g Air resistance, Friction, Water resistance
A force that acts when not touching something
Non-contact force
E.g force between magnets, Gravity
How do you measure force?
With a Newtonmeter
Newtons (N)
The word that describes paired forces
Interaction Pairs
Hooke’s Law
Hooke’s Law is if the Extension doubles when the force is doubled, it obeys Hooke’s Law.
How can you reduce friction
You can lubricate the surface the object is on
E.g make it smoother/less aggressive
What are Drag Forces
A drag force almost drags you back.
E.g Water resistance almost drags back a dolphin while swimming. (Makes it harder).
A parachute can create a drag force when falling
You can reduce a drag force by streamlining you body to make sure you travel through less particles.
The difference between weight and mass
Weight is measured in Newtons. Mass is the amount of ‘stuff’ something is made out of. Mass is measured in kg.
Balanced Forces
When forces have the same strength but going in opposite directions
Unbalanced Forces
The forces acting on a car are unbalanced. The driving force (thrust) is much bigger than the resistive force (air resistance). This causes the car to go forward
Waves
Transverse waves are at 90 degrees and look like waves.
Longitudinal waves are at 180 degrees and are vertical lines.
Reflecting Waves
The wave going into a barrier is the incident ray. The one coming out is the reflected ray
What happens when waves are put together
They superpose. (When they ads up or cancel out).
Vaccum
An empty space with no particles in it.
E.g Space is a vaccum
What do sound waves need to be able to travel
They need a medium.
Solid liquid or gas.
