Physics 30 Flashcards
Momentum and Impulse,
What is momentum?
And the equation?
“mass in motion”
p=mv in Ns or Kg x m/s
What is impulse?
And the equation?
Change in momentum
Δp= FΔt = m( vf-vi )
What is the area under a force vs time graph?
Impulse
What is the conservation of momentum?
What is an isolated system?
P before = P after
Within an isolated system.
An isolated system is when no external forces are present.
What types of 1D collisions are there?
There equations
Two objects collide and couple/stick
Two objects collide and move off separetely
two objects together fly together apart in opposite direction. Often from a stand still. *recoil
M1Vi1 + M2Vi2 = Mtotal Vf
M1Vi1 + M2Vi2 = M1Vf1 + M2Vf2
0 = M1Vf1 + M2Vf2
What are the steps for a 2D collision?
- Separate x + y vectors
- Right Triangle (head to tail)
- Find the resultant ( hypotenuse )
- Find angle
- Compass
What is elastic vs inelastic collisions?
An elastic collision conserves Ek
-> total Ek before = total Ek after
An inelastic doesn’t
-> often when two objects collide and stick
What are the three methods of transfer?
Friction- rubbing two surfaces together
Conduction- point contact
Induction- no touch and indirect transfer of electrons
In what direction does an electric field flow?
Between parallel plates does this value change?
from positive to negative
No
What does it mean when an atom of object is suspended in a parllel plate?
Fg= Fe
What direction does a magnetic field flow?
from the N into the south
What does your hand represent in hand rules?
Palm - Fm
Fingers- Field direction
Thumb - Direction of particle
Left hand- negative
Right hand - Positive
If the wire is coiled what is the hand rule?
Field is wrapped following wire
Thumb points N
What rules go along with bar magnets?
Wrist is N
Fingers S
What is Lenz’s Law?
Movement of magnet creates a B that opposes the movement
What is an EMR?
Acceleration of charged particles through perpendicular E and B fields
What are the wavelength of visible light?
Frequency is 10^15
Wavelength 10^-7
Red 800nm
Purple 350nm
What are the formulas for Michelson?
c=d/t ; d is the distance there and back
t=T/ number of sides of mirror
T=1/f
What is the same about EMR between different mediums?
Frequency
What angle do you use in refraction problems?
The angle between the normal and the ray
What is total internal reflection?
the minimum angle that causes a ray to reflect
When a light ray goes through a prism what occurs?
Light is separated into colors and the purple (smaller) wavelengths refract more
What occurs when light passes through a diffraction grating?
Light is separated into colors and the red ( longer wavelengths ) refract more
When can you use λ=dx/nl?
When the angle is less than 10 degrees
