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A moment of a force (or torque)

A moment of a force (or torque) is the product of the magnitude of the force and the perpendicular distance of the line of action of the force from the axis


couple

The torque due to a couple is the product of one of forces and the separation between them.


The centre of gravity

The centre of gravity of a body is the point through which its weight acts. Were it to be supported at that point there would be no net gravitational moment acting on the body.


centre of mass

The centre of mass of a body is the point through which its mass acts. In the absence of a pivot a body acts as if it were pivoted at its centre of mass.


Absolute zero

Is the temperature at which the pressure and volume of an ideal gas would be zero. All vibrational motion of the particles would cease. It is 0K (273^{o}C)


principle of moments

The principle of moments states that for a body to be in equilibrium, the sum of the clockwise moments about any axis is equal to the sum of the anticlockwise moments about that same axis.


Newton’s First Law of Motion

Every body continues in its state of rest or uniform motion in a straight line unless acted upon by an external force.


Newton’s Second Law of Motion

The rate of change of momentum of a body is directly proportional to the force acting upon it and takes place in the direction of the force.


Newton’s Third Law of Motion

Whenever a body A exerts a force on a body B, body B exerts a force of equal magnitude but opposite direction on body A.


Principle of Conservation of Linear Momentum

The Principle of Conservation of Linear Momentum states that the total linear momentum of a system of interacting bodies, on which no external forces are acting, remains constant.


Specific heat capacity

Specific heat capacity of a substance is the heat energy required to raise the temperature of one kilogram of that substance by one degree Kelvin.


specific latent heat of fusion

The specific latent heat of fusion of a substance is the energy required to change the state of one kilogram of the substance in its solid state to the liquid state without raising its temperature above its melting point.


specific latent heat of vaporization

The specific latent heat of vaporization of a substance is the energy required to change the state of one kilogram of the substance in its liquid state to the gaseous state without raising its temperature above its boiling point.


What is the equation of state?

pV = nRT
where: p = pressure V = volume n = number of moles R = molar gas constant T = absolute temperature (measured in Kelvin – make sure you can convert from Celsius to Kelvin and vice versa!)) 

What is the equation for kinetic energy?

E_{K} = ½ mv^{2}


What is the equation for change in gravitational potential energy?

delta Ep = mg delta h


What conditions must be met for you to apply Newton’s equations of motion to a body?

The body must be under constant acceleration conditions (e.g. falling under gravity).


What is the equation for momentum?

p = mv
where: p = momentum (Ns) m = mass (kg) v = velocity (m/s) 