GCSE Physics OCR B J259

In solving quantitative problems, students should be able correctly to recall, and apply the following relationships, using standard SI units:

force = mass × acceleration (P4.3.12, P4.3.13)

kinetic energy = 0.5 × mass × (speed)² (P4.4.3)

**momentum = mass × velocity(P4.3.4.) (P4.3.13) **

work done = force × distance (along the line of action of the force) (P4.4.2)

power = energy ÷ time (P3.4.2, P4.4.9)

efficiency = useful energy transferred ÷ total energy transferred (P2.1.8)

weight = mass × gravitational field strength (g) (P4.1.7)

In a gravity field: gravitational potential energy = mass × gravitational field strength (g) × height (P4.4.4)

force exerted by a spring = extension × spring constant (P6.3.5)

moment of a force = force × distance (normal to direction of the force) (P4.3.9)

average speed = distance ÷ time (P4.2.1)

acceleration = change in speed ÷ time taken(P4.2.6a)

wave speed = frequency × wavelength (P1.3.6)

charge = current × time (P3.2.2)

potential difference = current × resistance (P3.2.4a)

power = potential difference × current = (current)² × resistance (P3.4.4)

energy transferred (work done) = power × time = charge flow × potential difference (P2.1.3, P3.4.3)

density = mass ÷ volume (P6.1.2)

pressure = force normal to a surface ÷ area of that surface (P6.4.2)

potential difference = work done (energy transferred) ÷ charge (P3.3.1)

In addition, students should be able correctly to select from a list and apply the following relationships:

(final speed)² – (initial speed)² = 2 × acceleration × distance (P4.2.7)

change in internal energy = mass × specific heat capacity × change in temperature (P6.1.5a)

energy to cause a change of state = mass × specific latent heat (P6.1.6)

energy stored in a stretched spring = 1⁄2 × spring constant × (extension)² (P6.3.7)

force = magnetic flux density × current × length of conductor (P3.6.3)]

potential difference across primary coil × current in primary coil = potential difference across secondary coil × current in secondary coil (P3.4.5)

potential difference across primary coil ÷ potential difference across secondary coil = number of turns in primary coil ÷ number of turns in secondary coil (P3.7.8b)

for gases: pressure × volume = constant (for a given mass of gas and at a constant temperature) (P6.4.5)

**pressure due to a column of liquid = height of column × density of liquid × g (P6.4.8)

change in momentum = resultant force × time for which it acts (P4.3.5)**