Ms 2

Question 1

Demonstrate different types of charge

Answer 1

Charge rods of different plastics
Observation of attraction and repulsion

Or use charged gold leaf electroscope and look for rise and fall of leaves

Question 2

How things reduce injuries

Answer 2

Increases time of impact
Same momentum change with or without the thing
Reduces force
Force is rate of change of momentum

Question 3

How transformers work

Answer 3

Steps up/ down voltage
Primary current produces magnetic field 
Current changes (ac)
Causes magnetic field to change in core
Core strengthens field
Field lines cut secondary coil
Indices voltage 
Transformer does not work with dc

Question 4

How storm clouds discharge

Answer 4

Electrons move
Discharge to earth
Air conducts/ ionises
Lightning

Question 5

Person gets thrown backwards when throwing a ball

Answer 5

Conservation of momentum

Momentum of ball and person are equal and opposite as momentum was initially zero

Question 6

Why transformers need soft cores

Answer 6

Easily magnetise/ demagnetise

Magnetic field in core is able to alternate/ change

Question 7

What measures distance

Answer 7

Trundle wheel

Question 8

Advantages of charging paint and object

Answer 8

Opposite charge attract
Less paint wasted
Able to reach obscure places

Question 9

How evaporation leads to cooling

Answer 9

Temperature 🐟 energy
Liquid evaporates to gas 
Particles with higher KE leave surface
Reduce average KE in particles/ heat remaining
Reduces temperatures

Question 10

Person cools too quickly without foil sheet

Answer 10

Evaporation of sweat

Not generating heat anymore

Question 11

How coil sheet reduces heat loss

Answer 11

Reflects heat back

Barrier to reduce particle movements

Question 12

Moments force should be larger

Answer 12

Force of the ruler acts downwards

Question 13

Problems of waste disposal (7)

Answer 13

Radioactive
High activity
Long half life
Environmental harm
Expensive to contain
Location of storage is hard to find
Need to security and burial

Question 14

Why cooler balloons are smaller than hot balloons

Answer 14

Less KE on average 
Particles hit sides less often
Less force
Reduces tension on rubber
Balloon smaller

Question 15

Ways digital signals can carry more information

Answer 15

An additional level of strength
Increase frequencies/ higher bandwidth
Multiplexing/ use more than one channel

Increasing rate/ more hits in the same time
Quantisation by compressing data

Question 16

How does one tell he signal is digital

Answer 16

Has two values (on/off)

Question 17

Instrument to measure frequency

Answer 17

Oscilloscope

Data logged

Question 18

How force on wood from nail has a force on nail

Answer 18

Forces are equal as they are opposite forces (up and down)
Newtons 3rd law
Every action has an equal and opposite reaction

Question 19

Why man receives shock when he touches metal

Answer 19

Conductor
Voltage between man and earth
Transfer of electrons
Man has current in his body

Question 20

Why alpha is less penetrating than beta

Answer 20

Less penetrating/ shorter range
Have more charge 
Loses energy fast when ionising 
Ionises more 
Bigger/ more mass 
More likely to collide with atoms 
Lager force to slow down

Question 21

Positive to measuring lots of coins rather than one

Answer 21

Good way to measure small volumes

Taking large measurement can reduce errors

Question 22

Negative to measuring lots of coins rather than one

Answer 22

Not measuring what is required
Possible to make maths errors when adding and dividing
Not all the coins are the same/ some are worn/ bent/ anomalous