3.3 Optional application 1 – mechanics

3.3.1 MA: Dimensional analysis

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MA1Finding dimensions of quantities; checking for dimensional consistency.
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MA2Prediction of formulae; finding powers in potential formulae.

3.3.2 MB: Momentum and collisions

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MB1Conservation of momentum for linear motion and cases where velocities are given as one or two dimensional vectors (problems which require resolving).
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MB2Coefficient of restitution and Newton’s Experimental Law. Use in direct collisions and impacts with a fixed smooth surface. Problems which require resolving.
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MB3Impulse and its relation to momentum. Use of Ft=mv-mu . Problems which require resolving.
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MB4Impulse for variable forces. One dimension only. Use of I=Fdt .

3.3.3 MC: Work, energy and power

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MC1Work done by a force acting in the direction of motion or directly opposing the motion. Use of WD=Fd cosθ
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MC2Gravitational potential energy. Use in conservation of energy problems.
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MC3Kinetic energy. Use in conservation of energy problems.
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MC4

Hooke’s Law including using modulus of elasticity.

Use of T=kx or T=λlx

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MC5

Work done by a variable force. Use of WD=Fdx .

Use in conservation of energy problems.

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MC6

Elastic potential energy using modulus of elasticity. Use of EPE=kx22 and EPE=λx22l .

Use in conservation of energy problems.

3.3.4 MD: Circular motion

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MD1

Motion of a particle moving in a circle with constant speed (knowledge of radians assumed).

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MD2

Understand the definition of angular speed.

Use both radians and revolutions per unit time.

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MD3Relationships between speed, angular speed, radius and acceleration. Use of v=rω , a=rω2 and a=v2r
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MD4Use position, velocity and acceleration as vectors in the context of circular motion.
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MD5Conical pendulum, with one or two strings.
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MD6Circular motion in a vertical plane. Includes conditions to complete vertical circles. Use of conservation of energy in this context.

3.3.5 ME: Centres of mass and moments

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ME1Centre of mass for a system of particles.
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ME2Centre of mass for a composite body.
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ME3Centre of mass of a lamina by integration.
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ME4Centres of mass of bodies formed by rotating a region about the x -axis.
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ME5Conditions for sliding and toppling. Problems including suspension and on an inclined plane.
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ME6Determine the forces acting on a rigid body in equilibrium. Use of moments and couples.