physics formula
DESCRIPTION
AS LevelTRANSCRIPT
Formulae
1
Mechanical
ππ£πππππ π ππππ =πππ π‘ππππ
π‘πππ
π£ =π₯
π‘
π£ππππππ‘π¦ =πβππππ ππ πππ πππππππππ‘
π‘πππ π‘ππππ
π£ =βπ
βπ‘
π ππππ =π
π‘
ππ£πππππ πππππππππ‘πππ =πβππππ ππ π£ππππππ‘π¦
π‘πππ π‘ππππ
π =βπ£
βπ‘
πππ πππππππππ‘ = ππππ π’ππππ π‘βπ ππππβ
Equations of motion
π£ = π’ + ππ‘
π =1
2(π’ + π£)π‘
π = π’π‘ +1
2ππ‘2
π£2 = π’2 + 2ππ
Projectile
Vertical :
Time for maximum height, t
Formulae
2
π‘ =π’ sin π
π
Instantaneous height, y
π¦ = (π’ sin π) π‘ β1
2ππ‘
Total time taken, T
π =2π’ sin π
π
Horizontal :
Instantaneous displacement, x
π₯ = (π’ cos π) π‘
Range, R
π =π’2 sin 2π
π
Newtonβs Second Law of Motion
πΉ = ππ
Weight
π = ππ
Moment=force x distance from pivot
ππππππ‘ = πΉ Γ π₯1
Moment of anti-clockwise=Moment of clockwise
Work done
π = πΉ Γ π
π = πΉπ cos π
Gravitational Potential Energy
Formulae
3
πΆβππππ ππ π. π. π = π€πππβπ‘ Γ πβππππ ππ βπππβπ‘
πΈπ = ππβ
Kinetic Energy
πΎππππ‘ππ πΈπππππ¦ =1
2Γ πππ π Γ π ππππ2
πΈπ =1
2ππ£2
GPE βKE Transformation
πππππππ π ππ π. π. π = ππππ ππ π. π
Efficiency
ππππππππππ¦ = π’π πππ’π ππ’π‘ππ’π‘ ππππππ¦
π‘ππ‘ππ ππππ’π‘ ππππππ¦Γ 100%
Power
πππ€ππ =π€πππ ππππ
π‘πππ π‘ππππ
π =π
π‘
πππ€ππ = πππππ Γ π£ππππππ‘π¦
π = πΉ Γ π£
Linear momentum
ππππππ‘π’π = πππ π Γ π£ππππππ‘π¦
π = ππ£
In a closed system:
total momentum of object before collision=total momentum of object after collision
ππ΄π’π΄ + ππ΅π’π΅ = ππ΄π£π΄ + ππ΅π£π΅
Relative velocity
π£π΅ β π£π΄ = β(π’π΅ β π’π΄)
Change in momentum
Formulae
4
βπ = ππ β ππ
Impulse
βπ = πΉ Γ βπ‘
Density
ππππ ππ‘π¦ =πππ π
π£πππ’ππ
π =π
π
Pressure
ππππ π π’ππ =ππππππ πππππ
ππππ π β π πππ‘πππππ ππππ
π =πΉ
π΄
Pressure in a fluid
π = ππβ
Force constant
π =πΉ
π₯
Strain
π π‘ππππ =ππ₯π‘πππ πππ
ππππππππ πππππ‘β
π π‘ππππ =π₯
πΏ
Stress
π π‘πππ π =πππππ
ππππ π β π πππ‘πππππ ππππ
Formulae
5
π π‘πππ π =πΉ
π΄
Young modulus
πππ’ππ ππππ’ππ’π = π π‘πππ π
π π‘ππππ
πΈ =π
π
Elastic potential energy
πΈ =1
2πΉπ₯
πΈ =1
2ππ₯2
Electric field strength
πΈ =πΉ
π
πΈ =π
π
Current
ππ’πππππ‘ =πβππππ
π‘πππ
πβππππ = ππ’πππππ‘ Γ π‘πππ
βπ = πΌβπ‘
Resistance
πππ ππ π‘ππππ =πππ‘πππ‘πππ ππππππππππ
ππ’πππππ‘
π =π
πΌ
π = πΌπ
Electrical Power
πππ€ππ =ππππππ¦ π‘ππππ ππππππ
π‘πππ π‘ππππ
π =βπ
βπ‘
Formulae
6
βπ = πβπ
π = ππΌ
Power and Resistance
π = πΌ2π
π =π2
π
Calculating energy
πππ€ππ = ππ’πππππ‘ Γ π£πππ‘πππ
ππππππ¦ = πππ€ππ Γ π‘πππ
ππππππ¦ π‘ππππ ππππππ = ππ’πππππ‘ Γ π£πππ‘πππ Γ π‘πππ
βπ = πΌπβπ‘
Kirchhoffβs 1st Law
π΄Iin=π΄Iout
Kirchhoffβs 2nd
Law
π΄E=π΄V
Resistors in series
π = π 1 + π 2 + π 3 β¦ ..
Resistors in parallel
1
π =
1
π 1+
1
π 2+
1
π 3+ β―
V-I Graph
πππ ππ π‘ππππ =1
ππππππππ‘ ππ ππππβ
Resistivity
πππ ππ π‘ππ£ππ‘π¦ = πππ ππ π‘ππππ Γππππ π β π πππ‘πππππ ππππ
πππππ‘β
Formulae
7
π =π π΄
πΏ
Internal resistance
πΈ = πΌ(π + π)
Potential dividers
πππ’π‘ = βπ 2
π 1 + π 2β Γ πππ
Frequency
π =1
π
Period
π =1
π
Intensity
πππ‘πππ ππ‘π¦ =πππ€ππ
ππππ π β π πππ‘πππππ ππππ
Intensity and amplitude
πππ‘πππ ππ‘π¦
ππππππ‘π’ππ2= ππππ π‘πππ‘
Wave speed
π£ = π Γ π
Speed of light
π = ππ
Destructive interference
πππ‘β ππππππππππ =1
2π, 1
1
2π, 2
1
2π, β¦ ..
πππ‘β ππππππππππ = (π +1
2)π
Constructive interference
πππ‘β ππππππππππ = 0, π, 2π, 3π β¦.
Formulae
8
πππ‘β ππππππππππ = ππ
Young Double-slit
π =ππ₯
π·
a=slit separation
x=fringe separation
D=slit-to-screen distance
Determining π with a grating
π sin π = ππ
Air column (Open ends)
Formulae
9
πΏ =ππ
2
π =ππ£
2πΏ
Air column (Close ends)
Formulae
10
Error
π = 2(π2 β π1)
Sting
Formulae
11
Air Closed
Air open
Formulae
12
Radioactivity
Ξ±-decay
π΄π
π βπ΄ β 4π β 2
π +42
β
Ξ²-decay
10
π β11
π +0
β1π + ππππππ¦
Ξ³-emission