What is the formula for strain?
Strain = x/L Strain = extension/original length
What is the formula for stress?
Stress = force / area
σ = F/A
Why is the formula for the Young’s modulus?
Stress/strain
On a load extension graph, what represents the strain energy?
The area under the graph represents strain energy
What is an electron volt?
When an electron is accelerated through a potential difference of 1v, it’s change in kinetic energy is 1eV
What is the unit of energy?
A Joule
What is the unit of power?
A Watt, representing 1 joule per second
What is power?
Work done over time, measures in watts, 1 watt is 1 joule per second
What are the SI base units?
Mass: kilogram: kg Time: second: s Length: metre: m Electrical current: ampere: A Temperature: kelvin: K Amount of substance: mole: mol Luminous intensity: candela: cd
What is force in base units?
Newtons = kilogram x metre x second^-2
N = kgms^-2
What is the gradient on a displacement time graph?
Displacement / time = velocity
What is energy in base units?
Joule = kilogram x metre^2 x second^-2
J = kgm^2s^-2
What is power in base units?
Watt = kilogram x metre^2 x second^-3
W = kgm^2s^-3
What is frequency in base units?
Hertz = second^-1
Hz = s^-1
What is charge in base units?
Coulomb = amp x second
C = As
What is voltage in base units?
Volt = kilogram x meter^2 x second^-3 x amp^-1
V=kgm^2s^-3A^-1
What is resistance in base units?
Ohm = kilogram x meter^2 x second^-3 x amp^-2
Ω = kgm^2s^-3A^-2
What is the formula for strain?
Strain = change in length / length
ε = Δl/l
What factor is a deca-?
10^1
What factor is a hecto-?
10^2
What factor is a kilo-?
10^3
What factor is a mega-?
10^6
What factor is a giga-?
10^9
What factor is a tera-?
10^12
What factor is a peta-?
10^15
What factor is a deci-?
10^-1
What factor is a centi-?
10^-2
What factor is a micro-?
10^-6
What is the vector of speed?
Velocity
What is the vector of distance?
Displacement
What is the scalar of velocity?
Speed
What is the scalar of displacement?
Distance
What is the gradient of a velocity-time graph?
Velocity / time = acceleration
What is the area under a velocity-time graph?
Velocity x time = distance travelled
What is the gradient of a distance-time graph?
Distance / time = speed
What factor is nano-?
10^-9
What factor is pico-?
10^-12
What factor is femto-?
10^-15
What is the formula for velocity?
Velocity = displacement / time
What is formula for speed?
Speed = distance / time
What is a scalar quantity?
A quantity that has a magnitude only
What is a vector quantity?
A quantity that has magnitude and direction
What is the formula for average speed?
Average speed = total distance / total time
What is instantaneous speed?
The speed at any particular instant, can be found from the gradient of a tangent on a distance-time graph
What is the formula for acceleration?
Acceleration = change in velocity / time to change
a = Δv/Δt
Acceleration = (final velocity - initial velocity) / time
a=(v-u)/t
What is the gradient on a velocity-time graph?
Change in velocity / change in time = acceleration
(delta)v/(delta)t = a
What is the area under a velocity-time graph?
Velocity x time = distance
What is Newton’s first law of motion?
An object will remain in equilibrium unless acted upon by a resultant force
What is Newton’s second law of motion?
If a resultant force acts on an object, it is proportional the the acceleration if the mass remains constant
Force = mass x acceleration
F=ma
What is Newton’s third law?
Every action has an equal and opposite reaction
Forces: Are equal Act in opposite direction Are the same type of force Act on different bodies
Which SUVAT doesn’t contain s?
v=u+at
Final velocity = initial velocity + acceleration x time
Which SUVAT doesn’t contain a?
s=((u+v)/2) x t
Displacement = ((initial velocity + final velocity)/2) x time
What does SUVAT stand for?
S= displacement (metres) U= initial velocity (metres per second) V= final velocity (metres per second) A= acceleration (metres per second per second) T= time (seconds)
Which SUVAT doesn’t use v?
s=ut+(1/2)at^2
Displacement = initial velocity x time + 1/2 acceleration x time^2
Which SUVAT doesn’t use t?
v^2 = u^2 +2as
Final velocity^2 = initial velocity^2 + 2 x acceleration x time
What is the formula for density?
p=m/V
Density = mass/volume
What properties must a stationary interference pattern have?
Both waves must have the same frequency and as such a constant phase difference
What is uniform motion?
Motion without acceleration
What is the formula for kinetic energy?
E(k)=1/2mv^2
Kinetic energy = 1/2 x mass x velocity^2
