Equations

Question 1

Acceleration

Answer 1

Change in velocity /time

Question 2

Weight (N)

Answer 2

Mass (KG) x gravitational strength field

Question 3

Moment (Nm)

Answer 3

Force (N) x perpendicular distance from force to pivot (m)

Question 4

Electrical power (W)

Answer 4

Current (A) x voltage (V)

Question 5

Energy transferred (J)

Answer 5

Current (A)x voltage (V) x time (s)

Question 6

Voltage (V)

Answer 6

Current (A) x resistance (ohms)

Question 7

Charge (C)

Answer 7

Current (A) x time (s)

Question 8

Speed (waves) (m/s)

Answer 8

Frequency (Hz) x wavelength (m)

Question 9

Snell’s law (n)

Answer 9

Sin i / sin r

Question 10

Sin c (critical angle)

Answer 10

1 / n

Question 11

Efficiency

Answer 11

Useful energy output / total energy input

Question 12

Work done (J)

Answer 12

Force (N) x distance moved (m)

Question 13

Power (W)

Answer 13

Work done (J) / time taken (s)

Question 14

Kinetic energy (J)

Answer 14

1/2 x mass (KG) x speed*(m/s)

Question 15

GPE

Answer 15

Mass x gravity x height

Question 16

Density (g/cm3)

Answer 16

Mass (KG)/ volume (cm3)

Question 17

Pressure

Answer 17

Force / area

Question 18

Pressure difference (Pa)

Answer 18

Height (m) x density (g/cm3) x gravity

Question 19

Speed (m/s)

Answer 19

Distance (m) / time (s)

Question 20

Force (N)

Answer 20

Mass (KG) x acceleration (m/s2)