1.3 - Mechanics

Use the uniformly accelerated motion equations in one dimension: s = (u + v)t/2, v = u + at, s = ut + ½at², and v² = u² + 2as.

Use - uniform acceleration equations to connect the rule to the data and decision in the question.

This matters because - uniform acceleration equations determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - uniform acceleration equations to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: use the formula and units given in the question, show the substitution and interpret the result; the calculation alone is not the conclusion.

Be able to draw and interpret displacement-time, velocity-time and acceleration- time graphs.

Use - motion graphs to connect the rule to the data and decision in the question.

This matters because - motion graphs determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - motion graphs to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Motion graphs is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Know the physical quantities derived from the slopes and areas of displacement- time, velocity-time and acceleration-time graphs, including cases of non-uniform acceleration and understand how to use the quantities.

Use - gradients and areas of motion graphs to connect the rule to the data and decision in the question.

This matters because - gradients and areas of motion graphs determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - gradients and areas of motion graphs to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Gradients and areas of motion graphs is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Understand scalar and vector quantities and know examples of each type of quantity and recognise vector notation.

Use - scalars and vectors to connect the rule to the data and decision in the question.

This matters because - scalars and vectors determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - scalars and vectors to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Scalars and vectors is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Be able to resolve a vector into two components at right angles to each other by drawing and by calculation.

Use - resolving vectors to connect the rule to the data and decision in the question.

This matters because - resolving vectors determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - resolving vectors to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Resolving vectors is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Be able to find the resultant of two coplanar vectors at any angle to each other by drawing, and at right angles to each other by calculation.

Use - resultant vectors to connect the rule to the data and decision in the question.

This matters because - resultant vectors determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - resultant vectors to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Resultant vectors is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Understand how to make use of the independence of vertical and horizontal motion of a projectile moving freely under gravity.

Use - projectile motion components to connect the rule to the data and decision in the question.

This matters because - projectile motion components determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - projectile motion components to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Projectile motion components is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Be able to draw and interpret free-body force diagrams to represent forces on a particle or on an extended but rigid body using the concept of centre of gravity of an extended body.

Use - free-body force diagrams to connect the rule to the data and decision in the question.

This matters because - free-body force diagrams determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - free-body force diagrams to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Free-body force diagrams is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Be able to use the equation ∑F = ma, and understand how to use this equation in situations where m is constant (Newton’s second law of motion), including Newton’s first law of motion where a = 0, objects at rest or travelling at constant velocity Use of the term ‘terminal velocity’ is expected.

Use - newton’s second law and terminal velocity to connect the rule to the data and decision in the question.

This matters because - newton’s second law and terminal velocity determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - newton’s second law and terminal velocity to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Newton’s second law and terminal velocity is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Use gravitational field strength g = F/m and weight W = mg.

Use - gravitational field strength and weight to connect the rule to the data and decision in the question.

This matters because - gravitational field strength and weight determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - gravitational field strength and weight to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Gravitational field strength and weight is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

CORE PRACTICAL 1: Determine the acceleration of a freely-falling object.

Use - core practical 1 - freely-falling object acceleration to connect the rule to the data and decision in the question.

This matters because - core practical 1 - freely-falling object acceleration determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - core practical 1 - freely-falling object acceleration to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Core Practical 1 - freely-falling object acceleration is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Know and understand Newton’s third law of motion and know the properties of pairs of forces in an interaction between two bodies.

Use - newton’s third law and force pairs to connect the rule to the data and decision in the question.

This matters because - newton’s third law and force pairs determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - newton’s third law and force pairs to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Newton’s third law and force pairs is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Understand that momentum is defined as p = mv.

Use - momentum to connect the rule to the data and decision in the question.

This matters because - momentum determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - momentum to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Momentum is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Know the principle of conservation of linear momentum, understand how to relate this to Newton’s laws of motion and understand how to apply this to problems in one dimension.

Use - conservation of linear momentum to connect the rule to the data and decision in the question.

This matters because - conservation of linear momentum determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - conservation of linear momentum to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Conservation of linear momentum is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Be able to use the equation for the moment of a force, moment of force = Fx where x is the perpendicular distance between the line of action of the force and the axis of rotation.

Use - moment of a force to connect the rule to the data and decision in the question.

This matters because - moment of a force determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - moment of a force to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Moment of a force is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Be able to use the concept of centre of gravity of an extended body and apply the principle of moments to an extended body in equilibrium.

Use - centre of gravity and moments in equilibrium to connect the rule to the data and decision in the question.

This matters because - centre of gravity and moments in equilibrium determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - centre of gravity and moments in equilibrium to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Centre of gravity and moments in equilibrium is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Be able to use the equation for work ∆W = F∆s, including calculations when the force is not along the line of motion.

Use - work done to connect the rule to the data and decision in the question.

This matters because - work done determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - work done to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Work done is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Use Ek = ½mv² for the kinetic energy of a body.

Use - kinetic energy to connect the rule to the data and decision in the question.

This matters because - kinetic energy determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - kinetic energy to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Kinetic energy is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Be able to use the equation ∆Egrav = mg∆h for the difference in gravitational potential energy near the Earth’s surface.

Use - gravitational potential energy to connect the rule to the data and decision in the question.

This matters because - gravitational potential energy determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - gravitational potential energy to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Gravitational potential energy is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Know, and understand how to apply, the principle of conservation of energy including use of work done, gravitational potential energy and kinetic energy.

Use - conservation of energy to connect the rule to the data and decision in the question.

This matters because - conservation of energy determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - conservation of energy to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Conservation of energy is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Use P = E/t and P = W/t to relate power, time, energy transferred and work done.

Use - power, time and energy transfer to connect the rule to the data and decision in the question.

This matters because - power, time and energy transfer determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - power, time and energy transfer to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Power, time and energy transfer is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Be able to use the equations useful energy output efficiency = total energy input and useful power output efficiency = total power input.

Use - efficiency equations to connect the rule to the data and decision in the question.

This matters because - efficiency equations determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - efficiency equations to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: use the formula and units given in the question, show the substitution and interpret the result; the calculation alone is not the conclusion.