Physics Overall Flashcards
(35 cards)
Formula for Density?
Density=mass/volume
Formula for speed and acceleration?
Speed = distance / time
Acceleration = change in velocity / change in time
Formula for weight?
Weight = mass x gravitational field strength
Formula for force involving mass?
Force = mass x Acceleration
What is the formula for Hooke’s law?
What is meant by the term limit of proportionality?
Force = spring constant x amount of extension (meters)
Limit of proportionality is the maximum force that can be applied on a spring before the amount of extension is no longer proportional to the force.
What is the moment of a force and what is its formula?
The moment of a force is the measure of its turning effect.
Moment (Nm) = force(N) x perpendicular distance from pivot (meters)
What is the center of gravity?
The center of gravity is where the total mass of an object is concentrated.
Formula for momentum and its Unit?
Kg m/s
Momentum = mass x velocity
What is impulse and what is its formula?
Impulse is the time for which a force acts on an object.
Impulse = force x time
What is resultant force and what is the formula?
The resultant force is the change in momentum per unit time.
F = change in momentum/time
What is kinetic and gravitational potential energy and what are the formulas.
Kinetic energy is the energy an object possesses due to its motion. Gravitational potential energy is the energy an object has due to its height.
Kinetic energy = 1/2 x mass x v squared
Gravitational potential = mass x gravity x height
What is work and what is the formula?
Work is the energy transfer.
Work = force x displacement
Or
Work = change in energy
Formula for efficiency
Efficiency% = (useful energy or power output/total energy or power input) x 100
What is Power and what is the formula?
Power is the work done per unit time
P = Work or energy change / time (s)
What is pressure and what is the formula?
Pressure is the force per unit area.
Pressure = force/area
How to convert temperature between kelvin and Celsius?
Celsius + 273
What is Boyles law
The pressure of a gas is inversely proportional to the volume when the temperature is constant.
What is the specific heat capacity and what is the formula?
The specific heat capacity is the amount of energy needed to raise the temperature of 1kg of a given body by 1 degree Celsius.
Specific heat capacity = change in heat energy (J)/(mass x change in temperature)
Waves transfer energy without transferring matter. What is the wavefront, wavelength, frequency, crest (peak), trough, amplitude and wave speed?
Wavefront - Front line of the wave.
Wavelength - distance between two crests.
Frequency - how many waves happen in a second measured in hertz.
Crest - the top part of the wave.
Trough - the bottom part of the wave.
Amplitude - the maximum displacement of the wave.
Wave speed - how fast a wave travels through a medium.
Describe Fleming right hand rule.
What direction does conventional current move?
Thumb - direction of force
Index finger - direction of field, north to south
Middle finger - direction of current
Conventional current flows from positive to negative, opposite to actual flow.
Describe the right hand grip rule 1 and 2.
Rule 1, thumb = conventional current + to -
Fingers are the magnetic field direction.
Rule 2, thumb North Pole
Fingers are the conventional current direction in a coil.
Like currents and opposite currents attract or repel.
Like currents attract
Opposite currents repel
What is a commutator and what is a brush in generators?
Commutator changes direction of current in coil once every half revolution so coil rotates in the same direction and keeps moving.
The brush connects the commutator to the circuit and acts like a lubricant and is a good conductor. Made out of graphite.
What are alpha particles and give characteristics.
Alpha particles are a helium nucleus.
They are large and relatively slow and highly ionising which is the ability to remove electrons from atoms.
