AS1 Equations

Question 1

Moment Equation

Answer 1

Force x perpendicular distance from pivot

Question 2

Speed

Answer 2

Speed = distance/time

Question 3

Velocity

Answer 3

displacement/time

Question 4

SUVAT

Answer 4

V =U + AT
V^2 = U^2 + 2AS
S = UT + 1/2 AT^2
S = (1/2(U+V)) x T

Question 5

Resultant Force

Answer 5

Fr = ma

Question 6

Momentum

Answer 6

p = mv

Question 7

Force Momentum

Answer 7

change in momentum / time

Question 8

Impulse

Answer 8

I = Fxt = mv-mu = m(v-u)

Question 9

work done

Answer 9

work done = force x distance

Question 10

Kinetic Energy

Answer 10

1/2 x mass x velocity^2

Question 11

Gravitational Potential Energy

Answer 11

mass x gravity x height

Question 12

Power

Answer 12

p = IV
p = W/T
P = I^2 x R
P = W/Q
P = force x velocity

Question 13

Efficiency (energy)

Answer 13

useful energy output / total energy output

Question 14

Efficiency (power)

Answer 14

useful power output / total power input

Question 15

Charge

Answer 15

Q = It

Question 16

Current

Answer 16

Charge / time

Question 17

Total Charge (electrons)

Answer 17

Q = ne
n = number of electrons
e = charge of electron (1.6x10^-19)

Question 18

Voltage

Answer 18

V = W/Q
W = Work Done
Q = Charge

V = IR

Question 19

Resistivity

Answer 19

p = RA / L
R = pl / A

Question 20

EMF

Answer 20

E = V + Ir
V = Terminal P.d
Ir = Lost Volts

Question 20

Potential Divider Vout

Answer 20

Vout = R1 x Vin / R1 + R2
R1 is always the resistor the divider is across