physics Flashcards
prefixes??? start with 10^-12 to 10^9
pico -12 nano -9 micro -6 milli -3 centi -2 kilo +3 mega +6 giga 10+9
mks system
same as the SI system
the big 5 equations for uniformal acceleration?
d = 1/2 (Vi + Vf) t (no a) Vf = Vi + at (no d) d = Vi (t) + 1/2 (a) (t)^2 d = Vf (t) - 1/2 (a) t^2 Vf^2 = Vi^2 + 2ad
The slope of a position - time graph gives _________
velocity
The slope of velocity - time graph gives the ________
acceleration
the area under velocity - time graph gives the _________
displacement
what is the value (Decimal) of
sin0/30/45/60/90
cos0/30/45/60/90
sin= 0 / 0.5 / 0.7 / 0.9 / 1 cos = 1 / 0.9 / 0.7 / 0.5 / 0
Newton’s first law?
2nd law?
3rd law?
object moving = stays moving. object at rest = stays at rest unless there is Fnet acting on it.
2nd = Fnet = ma
3rd = Faction = Freaction
equation for Newton’s law of gravitation
Equation for g?
Fg = G(Mm/r^2) gm = G(Mm/r^2) g = G(M/r^2)
static and kinetic friction equations?
Fk = uk (Fn) Fs = us (Fn)
center of mass equation?
(m1x1 + m2x2 + m3x3…) / (m1+m2+m3…)
you will need to decide on a point that is x = 0
uniform in physics mean?
constant
what does uniform circular motion denotes?
constant speed and constant redius (also a is constant and only effect direction of velocity)
where does the acceleration point in a circular path?
toward the center of the circle
acceleration in a circular motion is called? equation?
centripetal accelerartion. directed toward the center. always perpendicular to v
ac = v^2 / r
Equation for centripetal acceleration?
ac = v^2 / r
magnitude of centripetal force equation?
Fc = (m)(ac) = mv^2 / r
what is the fulcrum? other name?
other name is pivot point. the point that the system spin or rotate around. the point that doesn’t move while the object rotates.
torque equation?
rFsin(o)
torque unit?
N.m
other equation for torque using lever arm?
t = L F (where l is the lever arm. or the shortest line that connect the pivot point with the force line to form a 90 degree angel).
equiliberium in physics mean
zero acceleration
static equiliberium mean? (in physics)
zero velocity
translational equilibruim?
F net is zero. and translational acceleration is zero
rotational equilibrium?
net torque is zero.
if equilibrium was mentioned without mentioing the exact type then its assumed?
its both rotational equilibrium and translational equilibrium
other name for rotational inertia?
moment of inertia
what is the moment of inertia? equation?
how resistent an object is to rotational acceleration.
torque (net) = I (alpha)
I = moment of inertia and
alpha = rotational acceleration
if the mass is closer to the center of rotation, then the moment of interia would be?
smaller.
if the mass is further to the center of rotation, then the moment of interia would be?
bigger
a sphere or a hollow ball, which have a larger moment of interia?
hallow ball
bigger moment of inertia means? _______ rotational acceleration
harder to rotate = smaller rotational acceleration (t =Ia)
which direction loosen? which direction of rotation tighten?
right tighty left loosey
intensive property?
unrelated to the amount of the substance. like color
extensive property
related to the amount of the substance, like thermal energy
what is the equation from the 1st law of thermo?
dalta E = Q - W
Dalta E = Q - W
where W is work done (by/on) the system
and Q is heat (into/out of) the system
heat into the system and work by the system
isochoric process?
constant volume
isobaric process? what happens?
constant pressure means Change in P is zero
isothermal process? what does it mean?
constant temp which mean constant KE avg which means constant E in dalta E = Q -W which means Q = W
adiabatic process?
no heat transfer (Q = 0)
What is a new equation that happens in isobaric processes? derivied from 1st law of thermo
Dalta E = Q - P Dalta V
W = F dalta h = PA dalta h = P dalta V
what is the new equation for an isochoric process? Dervied from the 1st law of thermo.
dalta E = Q (since Dalta V = 0 then W = 0 thus E = Q)
what is the new equation for an isothermic process? how did we get this equation?
since temp is constant. then based on P = nRT/ V there is an inverse relationship between V and P. and any work done on/by the system will result in heat out/into the system and to keep Temp constant = KE constant = Dalta E = 0 and thus Q = W
how does the four thermo process appear on a P-V diagram? isobar, isochore, isothermal, and adiabat.
density equation?
p = m/V
density S.I unit
kg/ m^3
fluid weight equation
w = pVg
what is specific gravity? equation?
the density of something relative to water. ratio.
d/ dwater
density of water?
1000 kg/m^3
equation of P gauge, and how we got it? equation for total pressure?
P = F/A = W/A = mg/A = pVg/A =pAdg/A =pdg Ptotal = Pgauge + P surface.
how to know how much of an object will submerge under water? equation?
same ration as the two densities.
pobject/pfluid = Vsubmerged / Total
flow rate equation?
f=Av
requirements for an ideal fluid flow?
incompressible
negligible viscosity
laminar (Streamline) flow
flow rate is steady
as the pressure of an ideal fluid goes up, the speed of the fluid __________
goes down
what is Bernoulli equation? When can it be applied? When can we eliminate P? When can we eliminate pgy?
with ideal fluid flow.
P + pgy1 + 1/2 pv^2 = ……
pgy is constant when its the same height.
P is constant and equal to Patm when exposed to the atmoshpere.
Why the two vehicles get toward each other? Explain.
Because the path between the two cars is narrower than on the outside, based on f=Av, this cuases the air to flow faster between the cars. Based on Branulli equation, this cuases an increase in 1/2pv^2 which causes the P to drop between the cars. Then the high P on the outside cuases the two cars to push toward each other.
electric force equation?
k Q q / r^2
electric potential equation
kQ/r
electric potential energy
E = kQ/r^2
electric potential energy (2 equations!)
kQq/r
or
qV
equation for the work done by an electric field?
change in electric potential energy.
