ap phyiscs exam

scalers vs vectors

distance vs displacement

has magnitude

• distance, mass, speed, temp, volume, energy

has magnitude and direction

• position, velocity, acceleration, displacement

distance: the total path taken

displacement: final - initial path

when do you use this equation v=x/t

when there is no acceleration, specifically in the x direction → so you can use it to find the displacement of an object after launch

direction of magnitude (north and east)

in quadrant one there is East on X-axis and North on Y-axis

• 0-45 is North of East

• 45-90 is East of North

Galilean transformations

• looking at systems with references

• x=x’+ut

• Vs=Um+U

• As=Am

When comparing 2 projectiles

• bigger angle has longer air time because of vertical velocity

• different angles → angle closer to 45 for higher horizontal velocity and closer to 90 for higher vertical velocity

hooke’s law, static and kinetic friction

hookes: F=-kx

Friction: Ff=(U)Fn

frequency vs periods, convert rpm to rad/s and rads relation to degrees

• periods: time/cycles

• frequency: cycles/time

rpm=revs per min

1 rev = 2 pi = 360 degrees

what is the equation for work and power (+units)

W= Fd = Fdcos(theta) = change in energy (KINETIC) in J

P= W/change in time = Fd/t = change in energy/time (KINETIC) in watts

Ug vs escape velocity vs gravitational field vs gravitational force

Ug

• gravitational potential energy is the PE of objects father from Earth’s surface

• Ug=(-GMm)/r

Escape Velocity

• minimum velocity needed for an object to escape the earth’s gravitational pull towards earth

• V=((2GM)/r)^1/2

gravitational field

• g=GM/r²

gravitational force

• F=(GMm)/r²

Remember that r=R+h

kelper’s 3rd law

T²/r³ = 4pi²/GM → M is the mass of sun

centripetal acceleration and force, velocity of UCM

Fn at the top of a circle vs bottom

minimum/weightless velocity in circle

• CA: a=v²/r

• CF: F=mv²/r

• V=(2pi)rf

Top: Fn= (mv²/r) - mg

bottom: Fn= (mv²/r) + mg

v=(gr)^1/2

analyze the force of a person in relation to a scale and elevator when going up and down

going up

• + acceleration, Fn increases, feels heavier, system of person and scale is bigger than earth to person

going down

• - acceleration, Fn decreases, feels lighter, system of earth to person is bigger than person and scale