Newton’s laws (P2.2) | OCR GCSE Combined Science A (Gateway Science) — Physics — Foundation (J250)

P2.2 Newton’s laws

Summary Newton’s laws of motion essentially define the means by which motion changes and the relationship between these changes in motion with force and mass. Underlying knowledge and understanding Learners should have an understanding of contact and non-contact forces influencing the motion of an object. They should be aware of the newton and that this is the unit of force. The three laws themselves will be new to the learners. Learners are expected to be able to use force arrows and have an understanding of balanced and unbalanced forces.

Common misconceptions Learners commonly have misconceptions about objects needing a net force for them to continue to move steadily and can struggle to understand that stationary objects also have forces acting on them. Difficulties faced by learners when trying to differentiate between scalar and vector quantities is the idea of objects with a changing direction not having a constant vector value, for example, objects moving in a circle. This issue also arises with the concept of momentum and changes in momentum of colliding objects.

Reference	Mathematical learning outcomes	Maths skills
$PM2.2i$	$force (N) = mass (kg) \times^{}$

recall and apply:

force (N) = mass (kg) \times^{}

M1a, M2a, M3a, M3b, M3c, M3d

recall and apply:

\text{work done (J)}=\text{force (N)}\times\text{distance (m) (along the line of action of the force)}

M1a, M2a, M3a, M3b, M3c, M3d

recall and apply:

\text{power (W)}=\frac{\text{work done (J)}}{\text{time (s)}}

M1a, M2a, M3a, M3b, M3c, M3d

Learning outcomes	To include	Maths	Working scientifically	Practical suggestions
$P2.2a recall examples of ways in which objects interact$	$electrostatics, gravity, magnetism and by contact (including normal contact force and friction)$
$P2.2b describe how such examples involve interactions between pairs of objects which produce a force on each object$
$P2.2c represent forces as vectors$	$drawing free body force diagrams to demonstrate understanding of forces acting as vectors$	$M5b$	$WS1.2a, WS1.2b, WS1.2c, WS1.2e, WS1.3a, WS1.3c, WS1.3e, WS1.3h, WS2a, WS2b, WS2d$	$Measurement of the velocity of ball bearings in glycerol at different temperatures or of differing sizes. (PAG P3)$
$P2.2d apply Newton’s first law to explain the motion of an object moving with uniform velocity and also an object where the speed and/or direction change$	$looking at forces on one body and resultant forces and their effects (qualitative only)$		$WS1.3e, WS2a$	$Demonstration of the behaviour of colliding gliders on a linear air track. (PAG P3) Use of balloon gliders to consider the effect of a force on a body.$
$P2.2i apply Newton’s Second Law in calculations relating forces, masses and accelerations$		$M1a, M2a, M3b, M3c, M3d$	$WS1.2a, WS1.2b, WS1.2c, WS1.2e, WS1.3a, WS1.3c, WS1.3e, WS1.3h, WS2a, WS2b, WS2c, WS2d$	$Use of light gates, weights and trolleys to investigate the link between force and acceleration. (PAG P2)$
$P2.2l use the relationship between work done, force, and distance moved along the line of action of the force and describe the energy transfer involved$		$M1a, M2a, M3a, M3b, M3c, M3d$	$WS1.4a, WS2a, WS2b$	$Measurement of work done by learners lifting weights or walking up stairs. (PAG P5)$
$P2.2m calculate relevant values of stored energy and energy transfers; convert between newton-metres and joules$		$M1c, M3c$	$WS1.4e, WS1.4f$
$P2.2n explain, with reference to examples, the definition of power as the rate at which energy is transferred$
$P2.2o recall and apply Newton’s Third Law$	$situations of equilibrium and non-equilibrium$

P2.2a recall examples of ways in which objects interact

electrostatics, gravity, magnetism and by contact (including normal contact force and friction)

P2.2b describe how such examples involve interactions between pairs of objects which produce a force on each object

P2.2c represent forces as vectors

drawing free body force diagrams to demonstrate understanding of forces acting as vectors

WS1.2a, WS1.2b, WS1.2c, WS1.2e, WS1.3a, WS1.3c, WS1.3e, WS1.3h, WS2a, WS2b, WS2d

Measurement of the velocity of ball bearings in glycerol at different temperatures or of differing sizes. (PAG P3)

P2.2d apply Newton’s first law to explain the motion of an object moving with uniform velocity and also an object where the speed and/or direction change

looking at forces on one body and resultant forces and their effects (qualitative only)

Demonstration of the behaviour of colliding gliders on a linear air track. (PAG P3) Use of balloon gliders to consider the effect of a force on a body.

P2.2i apply Newton’s Second Law in calculations relating forces, masses and accelerations

M1a, M2a, M3b, M3c, M3d

WS1.2a, WS1.2b, WS1.2c, WS1.2e, WS1.3a, WS1.3c, WS1.3e, WS1.3h, WS2a, WS2b, WS2c, WS2d

Use of light gates, weights and trolleys to investigate the link between force and acceleration. (PAG P2)

P2.2l use the relationship between work done, force, and distance moved along the line of action of the force and describe the energy transfer involved

M1a, M2a, M3a, M3b, M3c, M3d

Measurement of work done by learners lifting weights or walking up stairs. (PAG P5)

P2.2m calculate relevant values of stored energy and energy transfers; convert between newton-metres and joules

P2.2n explain, with reference to examples, the definition of power as the rate at which energy is transferred

P2.2o recall and apply Newton’s Third Law

situations of equilibrium and non-equilibrium

Newton’s laws

Next Steps

Learning Objectives