semester 2 final Flashcards
Kinetic energy equation
KE = 1/2mv^2
Potential gravitational energy equation
GPE = mgh
elastic energy equation
Eel = 1/2kx^2
what is work
a force applied over a distance
-the force has to be in the same direction of motion
what is power
work divided by time
what is the difference between work and power
work is force applied and power is force applied over time
define momentum
when you’re moving, momentum keeps you moving
object w a lot of momentum is hard to stop
-p=mv
define inertia
Fnet x t
I = F/t
what is impulse
the change in momentum
what is the law of conservation of momentum
the total momentum before a collision = the total momentum after a collision
what’s an elastic collision
colliding objects bounce off of one another
what’s an inelastic collision
colliding objects stick together
the area underneath a force vs time graph tells you what
Impulse or change in momentum
describe charging by conduction
charging a neutral object without touching it
describe charging by induction
taking a charged object and transferring that energy to uncharged objects, making the charges in the uncharged spheres separate
______ charges attract
opposite
_______ charges repel
like
what is electron affinity
the change in energy of a neutral atom when an electron is added
Charge of 1 electron
1 electron = -1.6 x 10^-19 C
what is Ohm’s law
V = IR
- v = voltage
- I= current
- r = resistors
define voltage
volts produce electric field to cause current to flow
define current
amount of charge that passes a spot in a given amount of time
define resistors
the only component in a circuit that reduces the amount of current that passes through that part of the circuit
what factors do affect the speed of mechanical waves
The medium
what factors don’t affect the speed of mechanical waves
Amplitude, wavelength, frequency, etc
describe the Doppler effect
the effect produced by a moving source of waves in which there is an apparent upward shift in frequency for observers towards whom the source is approaching and an apparent downward shift in frequency for observers from whom the source is receding
what is the wave equation
Frequency x wavelength
describe rotational inertia
resistance to change in rotating motion
what factors affect rotational inertia
- mass
- distribution of mass
- the farther the mass is located from the axis of rotation, the higher the rotational inertia*
what is angular momentum
L= Iw
L- angular momentum
I- rotational inertia
w- angular velocity
what is rotational speed
number of rotations in a certain amount of time
- aka frequency
- measured in RPM(revolutions per minute) or Hertz(revolutions per second)
what is a centripetal force
pulls together
what is a centrifugal force
pushes apart
define tangential velocity
V= 2pi(r)/time
law of universal gravitation
Fg = Gm1m2/r^2
cosF x D
work
work is measured in _____
Joules
power is measured in
joules/second
-aka a watt
to change momentum must apply ________
a net force
coefficient of restitution
measures elasticity of material
- 1 is perfectly elastic
- 0 is perfectly inelastic
6.25 x 10^18 e-
1 coulomb
F = k(q1q2)/r^2
coulomb’s law
I = change in Coulomb’s/change in time
current
Coulomb’s/second
amp
to produce electricity you need what?
a closed loop/circuit
things ____ about its internal axis
rotate
things _____ about an external axis
revolve
tangential speed
speed of something as it moves along a circular path
T= 1/f
period
Hooke’s Law
K= change in F/change in X
velocity in SHM
- positive to the right and negative to the left
- zero at the end points
- max at midpoint in either direction
acceleration in SHM
- positive when x is negative
- negative when x positive
- zero at the center
- max at the endpoints
period and frequency are ___________ related
inversely
To change the momentum of an object you must change either the ______or________
Mass or velocity
Ac= v^2/r
Centripetal acceleration
Fc= mv^2/r
Centripetal force
