Mechanics

Question 1

Scalar

Answer 1

Has no direction just amount of something

Question 2

Vector

Answer 2

Has magnitude and direction

Question 3

Scale drawing method

Answer 3

Make a scale drawing of two vectors, draw resultant vector and measure length and angle

Question 4

Horizontal component

Answer 4

VCos@=Vx

Question 5

Vx

Answer 5

VCos@

Question 6

Vertical component

Answer 6

VSin@=Vy

Question 7

Vy=

Answer 7

Vy=VSin@

Question 8

Formula for resolving forces

Answer 8

FH/F=Cos@ or FH=FCos@

FV/F=sin@ or FV=FSin@

Question 9

Principle of moments

Answer 9

For a body to be in equilibrium the sum of the clockwise moment about any point equals the sum of the clockwise moments about the same point

Question 10

A couple

Answer 10

A pair of forced of equal size which act parallel to each other in opposite directions

Question 11

Inertia

Answer 11

Greater mass of an object the greater its resistance to a change in velocity

Question 12

Centre of mass

Answer 12

Single point that you can consider its weight to act through

Question 13

Displacements

Answer 13

How far an objects travelled from starting point in given direction

Question 14

Free fall

Answer 14

Motion of an object undergoing an acceleration of g

Question 15

Newton’s First law

Answer 15

Velocity of an object will not change unless a resultant force acts on it

Question 16

Newton’s Second Law

Answer 16

More force you have acting on a mass, the more acceleration you get

Question 17

Newton’s third law

Answer 17

If an object exerts a force on object B, then object B exerts an equal but opposite force on object a

Question 18

Instantaneous velocity

Answer 18

Draw tangent to curve at that point and find gradient

Question 19

Average velocity

Answer 19

Divide total change in displacement by the total change in time

Question 20

Free fall

Answer 20

Motion of an object undergoing an acceleration of g

Question 21

Frictional forces

Answer 21

Always act opposite to motion
Never speed things up
Convert kinetic energy into Heat and sound

Question 22

Lift

Answer 22

Upwards force on an object through a fluid

Question 23

Elastic collision

Answer 23

Collision where momentum and kinetic energy are conserved

Question 24

Inelastic collision

Answer 24

Some kinetic energy converted into other forms but momentum conserved

Question 25

Newton’s 2nd law In momentum

Answer 25

Force is equal to rate of change in momentum | Rate of change in momentum directly proportional to resultant force F^t=^(mv)

Question 26

Impulse

Answer 26

Force x Time Ns Equal to change in momentum

Question 27

Work done

Answer 27

The amount of energy transferred

Question 28

Power

Answer 28

The rate of energy transfer

Question 29

Energy

Answer 29

Capacity or power to do work