formuals

Question 1

distance travelled =

Answer 1

distance travelled (m) = average speed (m/s) x time (s)
d = s x t

Question 2

acceleration=

Answer 2

acceleration (m/s*2) = change in velocity (m/s) ÷ time

a = (v-u) ÷ t

Question 3

final velocity =

Answer 3

final velocity (m/s) - initial velocity (m/s) = 2 x acceleration (m/s*2) x distance (m)
v*2 - u*2 = 2 x a x d

Question 4

force =

Answer 4

force (N) = mass (kg) x acceleration (m/s*2)

f = m x a

Question 5

weight =

Answer 5

weight (N) = mass (kg) x gravitational field strength (N/kg)

w = m x g

Question 6

momentum =

Answer 6

momentum (kg m/s) = mass (kg) x velocity (m/s)

p = m x v

Question 7

other formula for force =

Answer 7

force (N) = change in momentum (kg m/s) ÷ time (s)

f = (mv - mu) ÷ t

Question 8

kinetic energy =

Answer 8

kinetic energy (J) = 1/2 x mass (kg) x (velocity)*2 (m/s)*2
KE = 1/2 x m x v*2

Question 9

gravitational protentional energy =

Answer 9

gravitational protentional energy (J) = mass (kg) x gravitational field strength (N/kg) x height (m)
GPE = m x g x h

Question 10

work done =

Answer 10

work done (N/m) = braking force (N) x braking distance (m)
E = f x d

Question 11

efficiency =

Answer 11

efficiency (J) = useful energy transferred by devise(J) ÷ total energy supplied to devise (J)
answer should always be less then 1

Question 12

wave speed =

Answer 12

wave speed (m/s) = distance (m) ÷ time (s)
v = d ÷ t

Question 13

other formula for wave speed =

Answer 13

wave speed (m/s) = frequency (m/s) x wavelength (m)
v = f x λ

Question 14

Density =

Answer 14

density (kg/m3) = mass (kg) ÷ volume (m3)

Question 15

Hooke´s law:

Force =

Answer 15

k(spring constant) x X(extension in m)

Question 16

Power =

Answer 16

power (W) = work done (N/m) ÷ time taken (s)

P = E ÷ t

Question 17

Electrical Power =

Answer 17

electrical power (W) = current (amps (A)) x potential difference (volts (V)
P =IV

Question 18

Pressure in pascals=

Answer 18

pressure (Pa) = force (N) ÷ area (m*2)

p = f ÷ A

Question 19

Pressure due to a column of liquid =

Answer 19

pressure due to a column of liquid (Pa) = density (kg/m*3) x gravitational filed strength (N/kg) x height of liquid (m)

Question 20

Frequency =

Answer 20

Frequency (m/s) = 1 ÷ time period of wave (s)

Question 21

Angle of incidence =

Answer 21

angle of reflection

Question 22

Speed of light in air =

Answer 22

3 x 10^8 m/s

Question 23

Speed of light in glass =

Answer 23

2 x 10^8 m/s

Question 24

Speed of sound waves =

Answer 24

Speed of sound waves (m/s) =2 x distance (m) ÷ time for echo (s)

Question 25

Electric field intensity =

Answer 25

Electric field intensity = frequency (m/s) ÷ electric charge (amps(A))

Question 26

Resistance (ohms) =

Answer 26

Resistance (ohms) = voltage (volts(V)) ÷ current (amps(A))

Question 27

Current =

Answer 27

Current (amps(A)) = charge (coulombs) ÷ time (s)

Question 28

Voltage=

Answer 28

Voltage (volts(V)) = energy (J) ÷ charge (coulombs)

Question 29

Electromotive force =

Answer 29

lost volts + terminal potential difference

Question 30

In series –>

Answer 30

current stays the same, voltage divides

Question 31

In parallel–>

Answer 31

voltage stays the same, current divides

Question 32

Resistance (in series) =

Answer 32

R1 + R2 + R3

Question 33

Resistance (in parallel) =

Answer 33

1/R = 1/R1 + 1/R2 + 1/R3

Question 34

Charge =

Answer 34

charge (C) = current (amps(A))x time (s)

Question 35

other formula for power =

Answer 35

Power (W) = energy (J)÷ time (s)

Question 36

Potential divider =

Answer 36

V1/V2 = R1/R2

Question 37

V1 =

Answer 37

(R2 ÷ R1+R2) x V

Question 38

V2=

Answer 38

(R1 ÷ R1+R2) x V