genral

Question 1

Average speed

Answer 1

(ms)
distance (m)
——————-
time (s)

Question 2

Average velocity

Answer 2

(ms)
displacement (m)
—————————-
time (s)

Question 3

Period of a pendulum

Answer 3

(s)
total time (s)
————————-
number of swings
or
T = t
———–
number

Question 4

Acceleration

Answer 4

(ms^2)
final velocity – initial velocity
—————————————-
time (s)
or
a = v-u
—–
t

Question 5

Weight

Answer 5

Weght (N) = mass (kg) × gravitational field strength (ms-2)
Note: Earth’s gravitational field strength = 10 ms-2
F = mg

Question 6

Force

Answer 6

(N) = mass (kg) × acceleration (ms-2) F = ma

Question 7

Density

Answer 7

(kgm-3)
mass (kg)
—————–
volume (m3)

or
ρ = M
—–
V

Question 8

Hooke’s law

Answer 8

constant (Nm-1)= Force(N) : extension (m)

k = f
——
x

Question 9

Pressure

Answer 9

area (m2)
or
P = F
—
A

Question 10

Fluid Pressure

Answer 10

Fluid Pressure (Pa) = density (kgm-3) × gravitational field strength (ms-2 or Nkg-1) × height (m) P = ρgh

Question 11

Work

Answer 11

Work (J) = force (N) × distance moved (m) ΔE = Fd

Question 12

Power

Answer 12

Power (W) = work (J)
————-
time (s)
P = Δ E
——
t

Question 13

Kinetic Energy

Answer 13

Kinetic Energy (J) = ½ × mass (kg) × velocity^2 (ms-1)

KE = ½mv^2

Question 14

Gravitational potential energy

Answer 14

Gravitational potential energy (J)
= mass (kg) × gravitational field strength (ms-2 or Nkg-1) × height (m)

GPE = mgh

Question 15

Moment

Answer 15

Moment (Nm) = force (N) × perpendicular distance from pivot (m)

M = Fd

Question 16

Sum of clockwise moments

Answer 16

Sum of clockwise moments (Nm) = sum of anticlockwise moments (Nm)

F1d1 = F2d2

Question 17

Momentum

Answer 17

Momentum (kgms-1) = mass (kg) × velocity (ms-1)

p = mv

Question 18

Force (in terms of momentum)

Answer 18

Force (N) = change in
momentum(kgms-1)
—————————-
time (s)

F = Δp
—–
t

Question 19

Impulse

Answer 19

Impulse (kgms-1 or Ns) = change in momentum (kgms-1)

Ft = mv -mu

Question 20

Centripetal Force

Answer 20

Centripetal Force (N) =
mass (kg) × velocity^2 (ms-1)
—————————————-
radius (m)
F = mv2
——-
r

Question 21

Orbital Period

Answer 21

Orbital period(s) = 2 × π × radius (m)
————————-
velocity (ms-1)
T = 2πr
——-
v