Flashcards in Paper 2 Deck (37):
What are Newton’s 3 laws
1 = an object will remain stationary or moving at a constant speed and direction, unless a resultant force acts upon it.
2 = the acceleration of an object is directly proportional to the resultant force acting in it (F=ma).
3 = for every force there is an equal and opposite force.
What are contact and non-contact forces
Contact - when an object strikes another one (air resistance, friction)
Non contact - the opposite (magnetic force)
What is the difference between permanent and induced magnets
Permanent = magnets that have their atoms aligned all the time.
Induced = magnets that have their atoms aligned under the influence of an external magnet.
What is the equation involving force and distance
Work done = force x distance
How to increase the force in a magnetic system
Increase the current
Increase the strength of the magnet
Why does every car have a top speed
Because as you go faster the air resistance gets bigger up until the point where they’re equal.
At this point the forces are balanced and the car goes at a constant velocity.
What happens to the period of the wave as the frequency increases
What is the equation for elastic potential energy
0.5 x k x e^
0.5 x spring constant x extension^
What is the difference between thinking and breaking distance and what increases them.
Thinking = the distance travelled during your reaction time:
- high speed, drugs, tiredness, alcohol
Breaking = the distance travelled once your foot hits the brake:
- high speed, weather, surface of road, hot brakes, more mass
What is the equation for acceleration
Change in velocity / time
(End velocity - start velocity) / time
What happens to a current-carrying wire when placed in a magnetic field.
The magnetic field created by the current interacts with the field from the magnets and creates a force on the wire.
What is hookes law
The force applied to a spring is directly proportional to its extension... F=ke
What is reflection
When waves hit a smooth solid object they ‘bounce’ (reflect) off it.
What are longitudinal waves
The oscillations are parallel to the direction of energy transfer.
For example, sound waves.
They have compressions which are where the waves are close together.
They have rarefactions where the waves are spread out.
What is displacement
What do like and unlike poles do
Like poles repel
Unlike poles attract
What are the two suvat equations
If there’s no distance…
a = v-u / t
If there’s no time...
v^ = u^ + 2as
What is the equation for speed and what is difference between speed and velocity
Speed = distance / time
Velocity is just speed with a direction
What is a solenoid and what does its magnetic field look like
When you coil the wire.
It looks very similar to a bar magnets.
What is the equation that involves field strength, current and length
F = BIL
force = field strength x current x length
What can you say about the conservation of momentum
Momentum before = momentum after
What is the equation for pressure
Pressure = force / area
What is frequency
The number of waves passing a point each second
How to increase speed on a car
Use lighter materials
Make it streamlined
More powerful engine
Name the electromagnetic spectrum from smallest to largest
What does everything stand for in a suvat eqation
S = distance (m)
U = start velocity (m/s)
V = end velocity (m/s)
A = acceleration (m/s^)
T = time (s)
What is the involving frequency and wavelength
Wave speed = frequency x wavelength
How can you increase the strength of a an electromagnet
Adding more turns
Increasing the current
Adding an iron core
What is stopping distance
Breaking distance + thinking distance
What is the equation for weight
Weight = mass x gravity
What is the equation for momentum
Mass x velocity
How to find out the direction of the field lines in a wire
Right hand grip rule.
Thumb points in direction of current, fingers wrap around the direction of field lines.
What is an electromagnet
A wire around a nail connected to a battery
What are transverse waves
The oscillations are perpendicular to the direction of energy.
For example, water.
The crest is the top curve and the trough is the bottom curve.
The amplitude is from the centre to either a through or a crest.
The wavelength is from either a trough to a trough or crest to crest.
What is the difference between a scalar and a vector
Scalar = measurements have only have magnitude
Vector = measurements that have magnitude and direction
What is inertia
The tendency for objects to continue at the same speed in the same direction.