Physics paper 2 Flashcards
what is the typical speed for a person walking, running and cycling?
1.5m/s-w
3m/s-r
6m/s-c
describe motion in a circle
constant speed but changing velocity
state newtons first law
that a resultant force is needed for something to start moving speed up or slow down
what is inertia?
Tendency for motion to remain unchanged
rearrange the resultant force equation to find inertial mass.
f=ma -> m=f/a
what is the difference between velocity and distance time graphs
gradient of a DT graph is the speed.
gradient of a VT graph is the acceleration
state newton’s third law
for every action there is an equal and opposite reaction but in a different reaction
how are the oscillations in a transverse wave?
perpendicular to the direction of energy transfer
how are oscillations in a longitudinal wave?
parallel to the direction of energy
name all the properties of a wave
frequency
amplitude
wavelength
period
why would a wave bend towards the normal line?
if it crosses a boundary at an angle and speeds up when it is refracted
why would a wave bend away from the normal line
if it crosses a boundary at an angle and slows down
what type of waves are EM waves?
transverse
what are the 7 basic wave types? list their wave length as well
Radio-1m _ 10^4 micro-10^-2 infrared-10^-5 Vlight-10^-7 UV-10^-8 X-rays-10^-10 Gamma-10^-15
why do EM waves have a range of frequencies?
generated by a variety of changes in atoms and their nuclei
Name a use for each of the 7 basic wave types?
radio waves are used for communication.
microwaves are used by satellites and used to heat food
infrared is used for temp monitoring
visible light-transmit data through cables
uv- security pens to mark property or tanning
x-rays-used to picture broken bones
Gamma- used to treat cancer by killing the cells
what is a danger of uv?
damage surface skin cells into sunburn, can cause it to age prematurely as well.
Serious effects are blindness or cancer
how is radiation dose measured and what does it measure?
sieverts. It is a measure of the risk of harm of the body to radiation
what is a solenoid?
a wire wrapped into a coil.
What is an electromagnet? Give an example.
magnet who’s magnetic field can be turned on and off.
Solenoid.
how does wrapping the wire into a coil have an increased effect
field lines around each loop of wire line up with each other.Lots of field lines pointing in the same direction which makes them close.The closer the field lines are the stronger.
list the fingers used for flhr
thumb-motion
first finger-field
second finger-current
what is the motor effect?
the force exerted when a wire carrying current is put in between magnetic poles.
what happens to a wire when its in a magnetic field at certain angles?
90-full force
parallel-no force
in between-some force
what happens when you reverse direction of current or magnetic field
direction of force will reverse
work
the product of force and distance moved along the line of the action of the force
what is inversely proportional
a relationship between two variables where one decreases and the other increases
what is collision?
an event where two or more objects or particles come together with a resultant change of direction and energy.
what is momentum like in a closed system
total momentum before the even equals the total momentum after the even.momentum is conserved.
what does transmitted mean?
when waves are sent out from a source or pass through material
what is a refractive index?
a measure of the extent to which light is refracted by a material
definition of ionising
refers to radiation that causes atoms to lose or gain atoms becoming ions
what is flux density?
a measure of the density of the field lines around a magnet
what is a commutator?
device used to reverse direction of flow of an electric current in motors and generators
