Physics year 10 mocks Flashcards
Scalars
quantities that are fully described by a magnitude (or numerical value) alone
Vector
quantities that are fully described by both a magnitude and a direction
distance
is a scalar quantity that refers to how much ground an object has covered during its movement
displacement
is a vector quantity that refers to how far out of place an object is. it is the objects overall change in position
speed
is a scalar quantity that refers to how fast an object is moving (m/s)
velocity
a vector quantity that refers to the rate at which an object changes its position
Average velocity formula
change in position / time travelled
Acceleration formula
acceleration(m/s2)=(final velocity-velocity at the start(m/s) / time(s)
Mass and weight formula
weight(newtons)=mass(kg) x gravity(newton per kilo, N/kg)
earths gravity
9.8N/kg
Newton’s 1st law
an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force (air resistance)
Force
a force is a push or pull on an object
force formula
force=mass x acceleration
momentum formula
momentum(kgm/s)=mass(kg) x velocity(m/s)
Newton’s second law of motion
an object’s acceleration depend on the strength of the unbalanced force acting on it and the mass of the object
Newton’s third law of motion
for every action, there is an equal and opposite reaction
Energy types
thermal, kinetic, gravitational potential, chemical, sound, light, nuclear, elastic potential, electrical
Efficiency
a measure of how much of the energy supplied is transferred to useful energy
efficiency formula
useful energy out / total energy in x 100%
conduction
vibrations get passed on
convection
hot particles rise up and cold particles rush in to fill their place. Hot particles are less dense than cold particles
radiation
no particles needed, electromagnetic waves, black will absorb and silver will reflect
gravitational potential energy formula
mass x gravity x height(m)
kinetic energy
0.5 x mass x velocity2
what is energy measured in?
Joules
non-renewable resources are:
coal, oil, gas, nuclear
renewable resources are:
wind, tidal, solar, hydro-electric, geothermal, wave, biomass
how does a wave transfer energy?
vibrations
waves which don’t use vibrations to travel are?
electromagnetic waves
How do electromagnetic waves travel without the use of particles?
vibrations in an energy field
frequency is?
the number of waves made a second (Hz)
waves where energy is transferred perpendicular to vibrations
transverses
waves where energy is transferred parallel to vibrations
longitudinal
what does wave mean?
a wave is a way of transferring energy
wave velocity formula
wave frequency(Hz) x wavelength(m)
wave frequency formula
wave velocity(m/s) / wave length(m)
wave length formula
wave velocity(m/s) / wave frequency(Hz)
what is the incident angle?
the angle between a ray incident and the normal
what is the refracted angle?
the angle between the normal and the refracted ray inside the object
what are the 3 section of the ear called?
outer, middle and inner ear
How do we hear?
vibrations travel down the ear canal and cause the eardrum to vibrate. These vibrations move the small bones at the back of our ear called the malleus, incus and stapes. These vibrations get passed onto the cochlea which causes little hairs inside to move. this movement of the hairs creates electrical impulses which are brain interprets as sound
what frequencies are classed as ultrasound?
above 20’000Hz
what frequencies are classed as infrasound
below 20Hz
what is the frequency range of humans?
20 to 20’000Hz
what can longitudinal waves pass through?
solids, liquids and air
what can transverse waves pass through?
solids
what is total internal reflection?
when a wave can’t refract out of a material due to the large angle it hits the internal surface at
