equations (not on equation sheet) Flashcards
(31 cards)
average speed
total distance(m) /total time(s)
speed: m/s
average velocity
Δdisplacement(m) / time(s)
velocity: m/s
acceleration
Δvelocity(m/s) / time(s)
acceleration: m/s^2
the SUVAT equation that excludes u
s= vt - 1/2 at^2
thinking distance
speed(m/s) * reaction time(s)
distance: m
force when mass is constant
mass(kg) * acceleration(m/s^2)
Force: kg m/s^2
weight
mass(kg) * 9.81
weight: N
pressure in a fluid
depth(m) * 9.81 * density of fluid(kg/m^3)
pressure: Pa
upthrust caused by fluid
- 81 * density of fluid(kg/m^3) * height of object(m) * cross-sectional area of object (m^2)
upthrust: N
work done
force(N) * distance in the direction of the force(m)
work done: Nm or J
kinetic energy
1/2 * mass(kg) * velocity^2(m/s)
KE: J
Δgravitational potential energy
mass(kg) * Δheight(m) * 9.81
ΔGPE: J
velocity assuming KE=GPE
Square root(29.81height(m))
velocity: m/s
tensile stress
Force(N) / cross-sectional area(m^2)
stress: Pa
tensile strain
extension(m) / original length(m)
*100 for a %
no units
Young modulus
stress/strain
Young modulus: Pa
impulse
force(N) * time(s)
impulse: Ns
the equation for work done on an electron
electron charge * P.d(V) = 1/2 * mass(kg) * velocity^2(m/s)
work done: J
the voltage across a component
current through the component(A) * components resistance(Ω)
voltage: V
power of a component
P.d across component(V) * current through it(A)
power: W
e.m.f
terminal P.d(V) + lost volts(V)
e.m.f: V
an equation involving internal resistance
e.m.f(V) = current(A)Resistance of circuit(Ω) + current(A)internal resistance(Ω)
intensity
Power(W) / area(m^2)
intensity: W/m^2
refractive index
c (m/s) / speed of light in that material (m/s)
no units