PHYSICS

Question 1

Wave Speed

Answer 1

Wave speed (m/s) = Frequency (Hz) x Wavelength (m)

Question 2

Reflection

Answer 2

Angle of incidence = Angle of reflection

Question 3

Density

Answer 3

Density (kg/m3) = Mass (kg) / Volume (m3)

Question 4

Efficiency

Answer 4

Efficiency = Useful energy out / Total energy in

Question 5

Alpha Decay

Answer 5

Mass number decreases by 4, atomic number decreases by 2 (2 protons, 2 neutrons lost). Alpha particle (4/2) released

Question 6

Beta Decay

Answer 6

Mass number constant, atomic number increase by 1 (1 neutron turns into 1 proton). Beta particle (e-) released

Question 7

Velocity

Answer 7

v = s / t

Question 8

Acceleration

Answer 8

a = (v-u) / t

Question 9

Gravity Force (Weight)

Answer 9

W = mg

Question 10

Force

Answer 10

F = ma, F = △mom / t

Question 11

Work done

Answer 11

Work done (j) = Force (N) x Distance (m)

Question 12

Power (energy and force)

Answer 12

Power (W) = Work done (j) / Time (s)

Question 13

Pressure

Answer 13

Pressure (Pa) = Force (N) / Area (m2)

Question 14

△Gravitational Potential Energy

Answer 14

△Gravitational Potential Energy = Mass (kg) x △Height (m) x Gravitational field strength

Question 15

Kinetic energy

Answer 15

Kinetic energy (j) = 0.5 x Mass (kg) x Speed2 (m2/s2)

Question 16

Momentum

Answer 16

Momentum (kjm/s) = Mass (kg) x Velocity (m/s)

Question 17

Power (electricity)

Answer 17

P = IV, P = I2R, P = V2/R

Question 18

Charge, Current, Time

Answer 18

Q = It

Question 19

Energy Transfered, Charge, P.d

Answer 19

E = QV

Question 20

P.d, Current, Resistance

Answer 20

V = IR

Question 21

Total Resistance (2 in parallel)

Answer 21

Rt = Product / Sum

Question 22

Total Resistance (identical in Parallel)

Answer 22

Rt = R1 / n

Question 23

Transformer Equation

Answer 23

V1 / V2 = Turns1 / Turns2

Question 24

Resistance, P.d relationship (in series)

Answer 24

R1 / R2 = V1 / V2

Question 25

Current, Resistance and P.d (in series)

Answer 25

I1 = I2 = I3, Vt = V1 + V2, Rt = R1 + R2

Question 26

Current and P.d (in parallel)

Answer 26

It = I1 + I2, V1 = V2 = V3

Question 27

Energy

Answer 27

= ItV (current x time x voltage)

Question 28

Magnetic Force

Answer 28

Magnetic field x Current x Length (BIl)

Question 29

Elastic Potential Energy

Answer 29

0.5 x Spring Constant x e (extension/length) (0.5ke)

Question 30

Specific Heat Capacity

Answer 30

thermal energy / mass x delta temperature

Question 31

Hydrostatic Pressure

Answer 31

depth (height) x density x gravity (pgh)

Question 32

Frequency

Answer 32

1 / Period