D&R 2 Flashcards
What are the relationships for Work Done?
W = Fs
W = Fs cos•
W = § Fx dx
What is the relationship for Work Done in a spring?
W = 1/2 kx
What is the relationship for the total Work Done
W(tot) = DK
What are the relationships for Power and Work?
P = DW/Dt
W = Fs
P = F ds/dt
= Fv
W = {P2-P1} § F dt
What is the relationship for gravitational potential energy?
U = mgy
What is the relationship for elastic potential energy?
U = 1/2 kx^2
What is the relationship between force and potential energy
F = -dU/dt
What is the relationship for spring kinetic energy?
K = 1/2 kx^2
What is the relationship for the conservation of energy?
K + U + W = 0
What are the principles of conservation of energy?
Energy can neither be created nor destroyed
Energy can be converted from one form to another
What is the relationship for gravitational field strength?
g = GM/r^2
What is the relationship for the gravitational potential energy between two objects?
U = -G m1m2/r
What is the relationship for momentum?
p = mv
What is the relationship for impulse?
J = Ft
J = Dp
What is the principle of conservation of linear momentum?
The total linear momentum of an isolated system is conserved
What is an isolated system?
One with no net external forces
What are the relationships for conserved kinetic energy and momentum?
K: 1/2m1v0^2 = 1/2m1v1^2 + 1/2m2v2^2
p: m1v0 = m1v1 + m2v2
What makes a collision elastic?
The total K is conserved
What makes a collision COMPLETELY inelastic
When the objects stick together
What is the relationship for torque
Þ = Fr
What is the relationship for angular momentum?
L = rp
What is the relationship for rotational kinetic energy?
K = 1/2 Iw^2
What is torque?
The produce of a force with respect to O and its lever arm, the perpendicular
What is the relationship for moment of inertia of a point mass?
I = mr^2
What is the relationship for moment of inertia of a rod at centre
I = 1/12 ML^2
What is the relationship for moment of inertia of a rod at end
I = 1/3 ML^2
What is the relationship for moment of inertia of a plate at centre
I = 1/12 M(a^2 + b^2)
What is the relationship for moment of inertia of a plate at edge
I = 1/3 Ma^2
What is the relationship for moment of inertia of a hollow cylinder
I = 1/2 M(R1^2 + R2^2)
What is the relationship for moment of inertia of a solid cylinder
I = 1/2 MR^2
What is the relationship for moment of inertia of a thin hollow cylinder
I = MR^2
What is the relationship for moment of inertia of a solid sphere?
I = 2/3 MR^2
What is the relationship for moment of inertia of a hollow sphere?
I = 2/3MR^2
What is the relationship for the total torque?
Þ = I ą
(F = ma)
What is the relationship for total inertia?
I = § r^2 dm
What is an event?
An event is a physical “happening” that occurs at a particular place and time
What is an inertial frame of reference?
One for which Newton’s law of inertia is valid
What is Einsteins first postulate?
The principal of relativity: the laws of physics are the same for all inertial frames of reference
What is Einstein’s second postulate?
The speed of light in a vacuum is the same in all inertial frames of reference and is independent of the motion of the source
What was Einsteins thought experiment?
Acceleration is indistinguishable from gravity by experiment
What is the Lorentz factor?
y = 1/_/1-(v/c)^2
What is time dialation?
Time appears relatively and time intervals dial are in a non inertial frame of reference
What is the relationship for time dialation?
ť = t0/_/1-(v/c)^2 = yt0
What is length contraction?
Length appears relatively and contracts in non inertial frames of reference
(Length perpendicular to the direction of travel does not contract)
What is the relationship for length contraction?
ľ = l0 _/1-(v/c)^2
What are the Lorentz transformations?
x’ = y(x-ut)
t’ = y(t- ux/c^2)
vx’ = (vx - u)/(1-uvx/c^2)
What is the relationship for relativistic momentum?
p = ymv
What is the relationship for relativistic kinetic energy?
K = (y - 1)mc^2
What are the relationships for relativistic energy?
E = ymc
p = ymv
v=c
E = pc
