#20
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Components of a Vector if V = 34 m/sec ∠48° then Vi = 34 m/sec•(cos 48°); and VJ = 34 m/sec•(sin 48°) #4 Weight = m•g g = 9.81m/sec² near the surface of the Earth = 9.795 m/sec² in Fort Worth, TX Density = mass / volume
#21
Heating a Solid, Liquid or Gas Q = m•c•∆T (no phase changes!) Q = the heat added c = specific heat. ∆T = temperature change, K Linear Momentum momentum = p = m•v = mass • velocity momentum is conserved in collisions Center of Mass – point masses on a line xcm = Σ(mx) / Mtotal Angular Speed vs. Linear Speed Linear speed = v = r•ω = r • angular speed Pressure under Water P = ρ•g•h h = depth of water ρ = density of water
#23
ρ=
#7
m unit : kg / m 3 V
(
)
#25
Ave speed = distance / time = v = d/t Ave velocity = displacement / time = v = d/t Ave acceleration = change in velocity / time Friction Force FF = µ•FN
If the object is not moving, you are dealing with static friction and it can have any value from zero up to µs FN If the object is sliding, then you are dealing with kinetic friction and it will be constant and equal to µK FN
#26
#8
#28
Universal Gravitation
F =G
m1 m2 r2
G = 6.67 E-11 N m² / kg²
#9
τ = F•L•sin θ Where θ is the angle between F and L; unit: Nm
Newton's Second Law Fnet = ΣFExt = m•a Work = F•D•cos θ Where D is the distance moved and θ is the angle between F and the direction of motion, unit : J Power = rate of work done #30
Torque
#29
Mechanical Energy PEGrav = P = m•g•h KELinear = K = ½•m•v² Impulse = Change in Momentum F•∆t = ∆(m•v) Snell's Law n1•sin θ1 = n2•sin θ2 Index of Refraction n=c/v c = speed of light = 3 E+8 m/s Ideal Gas Law P•V = n•R•T n = # of moles of gas R = gas law constant = 8.31 J / K mole.
#11
#31
#12
#32
#16
Power =
Work time
unit : watt #34 Periodic Waves v = f •λ f=1/T
Efficiency = Workout / Energyin Mechanical Advantage = force out / force in