4.2 - Space, time and motion (A-Level Physics OCR B H557)

#4.2a(i)

the use of vectors to represent displacement, velocity and acceleration

#4.2a(ii)

the trajectory of a body moving under constant acceleration, in one or two dimensions

#4.2a(iii)

the independent effect of perpendicular components of a force

#4.2a(iv)

calculation of work done, including cases where the force is not parallel to the displacement

#4.2a(ix)

The principle of conservation of momentum; Newton's Third Law as a consequence.

#4.2a(v)

the principle of conservation of energy

#4.2a(vi)

power as rate of transfer of energy

#4.2a(vii)

measurement of displacement, velocity and acceleration

#4.2a(viii)

Newton's laws of motion

#4.2b

Make appropriate use of:

(i) the terms: displacement, speed, velocity, acceleration, force, mass, vector, scalar, work, energy, power, momentum, impulse

by sketching and interpreting:

(ii) graphs of accelerated motion; slope of displacement–time and velocity–time graphs; area underneath the line of a velocity–time graph

(iii) graphical representation of addition of vectors and changes in vector magnitude and direction.

#4.2c(i)

the resolution of a vector into two components at right angles to each other

#4.2c(ii)

the addition of two vectors, graphically and algebraically

algebraic calculations restricted to two perpendicular vectors

#4.2c(iii)

the kinematic equations for constant acceleration derivable from: $a = \dfrac{v-u}{t}$ and average velocity = $\dfrac{v+u}{2}$ :

$v = u + at$ $s= ut + \dfrac{1}{2}at^2$ $v^2 = u^2 + 2as$

#4.2c(iv)

momentum $p = mv$

#4.2c(ix)

gravitational potential energy = $mgh$

Learners will also be expected to recall this equation

#4.2c(v)

the equation $F = ma = \dfrac{Δ(mv)}{Δt}$ where the mass is constant

Learners will also be expected to recall the equation $F = ma$

#4.2c(vi)

the principle of conservation of momentum

one-dimensional problems only

#4.2c(vii)

work done $ΔE = FΔs$

*If displacement is at an angle θ to the force $ΔE = FΔ\cos{θ}$ *

#4.2c(viii)

kinetic energy = $\dfrac{1}{2}mv^2$

Learners will also be expected to recall this equation

#4.2c(x)

force, energy and power: power = $\dfrac{ΔE}{t} = Fv$

#4.2c(xi)

modelling changes of displacement and velocity in small discrete time steps, using a computational model or graphical representation of displacement and velocity vectors.

calculations restricted to zero or constant resultant force

#4.2d(i)

investigating the motion and collisions of objects using trolleys, air-track gliders etc. with data obtained from ticker timers, light gates, data-loggers and video techniques

links to 4.2a(vii), b(ii), c, PAG1

#4.2d(ii)

determining the acceleration of free fall, using trapdoor and electromagnet arrangement, lightgates or video technique

links to 4.2a(vii), b(ii), c, PAG1

#4.2d(iii)

investigating terminal velocity with experiments such as dropping a ball-bearing in a viscous liquid or dropping paper cones in air.

links to 4.2a(vii), b(ii), c, PAG1

A-Level Physics OCR B H557

4.2: Space, time and motion