Mechanics

Question 0

Average veloctity

Answer 0

The ratio of the change of displacement to the time taken.

Question 1

Displacement

Answer 1

The vector r from some arbitrary fixed point to the position of a particle i.e. The distance in a given direction.

Question 2

Average speed

Answer 2

The ratio of the total distance travelled d to the total time t taken - d/t

Question 3

Instantaneous velocity

Answer 3

The rate of change with time of the displacement vector. Instantaneous velocity is along the tangent to the path.

Question 4

Instantaneous speed

Answer 4

The rate of change with time of the distance traveled. It is equal to the magnitude of the instantaneous velocity vector.

Question 5

Average acceleration

Answer 5

The ratio of the change of the velocity vector to the time taken. This vector is in the same direction as (delta)v.

Question 6

Instantaneous acceleration

Answer 6

The rate of change with time of the velocity vector.

Question 7

Newtons 1st law

Answer 7

An object continues in uniform motion in a straight line or at rest until a resultant external force acts on it.

Question 8

Newtons 2nd Law

Answer 8

F = M x A
Force = Mass x Acceleration
The rate if change of momentum = (delta)p/(delta)t

Question 9

Newton’s 3rd Law

Answer 9

If body A exerts a force on body B, the body B exerts an equal but opposite force on body A.

Question 10

What is equilibrium?

Answer 10

It is not resultant force in any direction.

Question 11

Linear momentum

Answer 11

Is the mass of an object multiplied by its velocity.

Question 12

Impulse?

Answer 12

Is the force multiplied by time or charge of momentum.

Question 13

The law of conservation of linear momentum?

Answer 13

In an isolated system, momentum remains constant.

Question 14

Work?

Answer 14

Wok = force x distance moved in the direction of the force.

Question 15

Kinetic energy

Answer 15

Is the energy a body possesses by virtue of its motion.

Question 16

The principle of the conservation of energy?

Answer 16

Says that energy cannot be made or destroyed, only changed (transformed) from one form to another.

Question 17

Inelastic collision?

Answer 17

Is when there is a change in kinetic energy.

Question 18

Elastic collision?

Answer 18

Is when there is no change of kinetic energy.

Question 19

Power?

Answer 19

Is the rate at which energy is transferred (or the rate at which work is done).

Question 20

Efficiency?

Answer 20

Is the ratio of useful energy to the energy transferred (useful energy out/energy put in).

Question 21

Centripetal acceleration?

Answer 21

(Speed)^2/radius

Question 22

GPE =

Answer 22

M x G x H

Mass x Gravity (9.8ms^-2) x Height

Question 23

Kinetic energy =

Answer 23

1/2 x M x V^2

Half x Mass x velocity (squared)

Question 24

Plancks constant?

Answer 24

6.63 x 10^34 J

Question 25

E = H x f

Answer 25

Energy = Plancks constant x frequency

Question 26

Work =

Answer 26

Force x Distance