Further Mechanics

Question 1

What does the momentum of an object depend on?

Answer 1

mass & velocity

Question 2

What is the product of the two values of mass and velocity?

Answer 2

momentum of an object

Question 3

The word equation for linear momentum is:

Answer 3

mass x velocity = linear momentum

Question 4

The symbol equation for linear momentum is:

Answer 4

p (in kg ms^-1) = m (kg) x v (in ms^-1)

Question 5

Is linear momentum a vector/scalar quantity?

Answer 5

vector

Question 6

Is velocity a vector/scalar quantity?

Answer 6

vector

Question 7

Is mass a vector/scalar quantity?

Answer 7

scalar

Question 8

A vector quantity means that something has…

Answer 8

size (magnitude) and direction

Question 9

A scalar quantity means that something has…

Answer 9

only size (magnitude)

Question 10

Assuming no external forces act…

Answer 10

momentum is ALWAYS conserved.

Question 11

The total momentum of two objects before they collide =

Answer 11

the total momentum after the collision.

Question 12

Collisions can be…

Answer 12

elastic or inelastic.

Question 13

An elastic collision is where…

Answer 13

momentum is conserved and kinetic energy is conserved.

Question 14

No ………… energy is conseved

Question 14

What happens in an inelastic collision?

Answer 14

Some energy is dissipated as heat/light/sound etc.

Question 15

What is the difference between kinetic energy before a collision and the kinetic energy afterwards?

Answer 15

The energy dissipated as heat/sound etc.

Question 16

What is Newton’s 1st Law?

Answer 16

If a body continues in its state of rest or uniform (unaccelerated) motion in a straight line unless acted upon by some resultant external force.

Question 17

What is the resultant force acting on a body if it is not accelerating?

Answer 17

Zero.

Question 18

When is the resultant force zero?

Answer 18

When a body is moving at a constant speed in a straight line or when is not moving.

Question 19

Just because the resultant force is zero,…

Answer 19

it does not mean that there are not any forces acting upon it.

Question 20

The 1st law also expresses the idea of what?

Answer 20

inertia

Question 21

What is inertia?

Answer 21

The reluctance of a body to start or stop moving / for its motion to be changed.

Question 22

A body of large mass is difficult to start or stop and therefore…

Answer 22

it has a large inertia.

Question 23

The mass of a body is a measure of:

Answer 23

its inertia.

Question 24

Linear momentum is what?

Answer 24

like, inertia it is a measure of resistance to change of motion.

Question 25

If 2 bodies of different masses have a common velocity. Which is more difficult to stop/slow down?

Answer 25

The heavier one.

Question 26

Newton's 2nd Law is?

Answer 26

"The rate of change of momentum is directly proportional to the resultant force acting on the body and it takes place in same direction as the force."

Question 27

resultant force (F) = mass (m) x acceleration (a) when mass is what?

Answer 27

constant

Question 28

resultant force =

Answer 28

mass x acceleration

Question 29

ma = what?

Answer 29

the resultant force of an object

Question 30

the vector sum of all the forces adds up to make the....

Answer 30

resultant force.

Question 31

Force is measured in:

Answer 31

Newtons (N)

Question 32

Mass is measured in:

Answer 32

Kilograms (kg)

Question 33

Acceleration, (a) is always measured in:

Answer 33

metres per second per second (ms^-2)

Question 34

Acceleration is always in the ...... direction as the ........ force.

Answer 34

SAME resultant force

Question 35

Impulse =

Answer 35

change in momentum

Question 36

F = (mv - mu)/t means what?

Answer 36

rate of change of momentum

Question 37

Impulse is defined through symbols as:

Answer 37

Ft (force x time)

Question 38

Units of impulse are:

Answer 38

Newton seconds (Ns)

Question 39

On force-time graph, how is the impulse found?

Answer 39

the area underneath the line

Question 40

What is Newton's 3rd law?

Answer 40

If body A exerts a force on body B then body B exerts the equal but opposite force on body A. (ie: action force and reaction force are equal but opposite)

Question 41

mass flow rate =

Answer 41

mass / time (m/t)

Question 42

mass = volume x density (in symbols?)

Answer 42

m = Vp

Question 43

volume = area x length (in symbols?)

Answer 43

V = AL

Question 44

resultant force equation (NOT on formula sheet)

Answer 44

pAv^2

Question 45

volume flow rate =

Answer 45

V/t and vA

Question 46

if something is energy/time what do you need to work out (not energy)

Answer 46

POWER

Question 47

on a stress/strain graph what does the steel line look like?

Answer 47

diagonally straight up then curved, goes higher up than rubber (like an r)

Question 48

on a stress/strain graph what does the rubber line look like?

Answer 48

almost vertically straight then curves up

Question 49

how much does Giga mean x10 to the?

Answer 49

9

Question 50

how to convert cm^3 into m^3

Answer 50

x10^-6

Question 51

in an elastic collision what is the impulse equivalent to?

Answer 51

2mv

Question 52

change in momentum =

Answer 52

mv [final] - (-mv) [initial]

Question 53

what does circular motion describe the motion of?

Answer 53

a body travelling at a constant speed in a circular path

Question 54

arc length =

Answer 54

rθ

Question 55

360° = how many radians?

Answer 55

2π

Question 56

in Physics what can't you leave the the distance of arc length in?

Answer 56

radians. MUST convert into number (3sf)

Question 57

what is angular velocity?

Answer 57

the Rate of Change of an Angle

Question 58

what is rate of change of an angle measured in?

Answer 58

rad s^-1

Question 59

what is angular speed?

Answer 59

the speed and angle rotates through per second

Question 60

linear speed is measured in?

Answer 60

ms^-1

Question 61

symbol for angular speed?

Answer 61

ω

Question 62

ω is measured in what?

Answer 62

rads s^-1