Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Physics > Paper 1 > Flashcards

Paper 1 Flashcards

1
Q

Explain why connecting the Earth wire to a metal case of a plug is Safe

A

Because if the live wire touches the metal case then the current will flow through the Earth wire rather than the human touching the case because the Earth wire has a lower resistance on the human

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Hey student investigated how the resistance of a piece of wire varies with length in a circuit with a variable resistance explain why the student needed to adjust a variable resistor each time she change the length of the wire

A

A variable resistor changes the resistance of the circuit so it keeps the current the same for each length of wire so that the temperature of the wire is constant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Why does 1 kg of a gas have much larger volume down 1 kg of a solid

A

Particles in a solid have strong forces of attraction which allows them to have a fit structure however particles in a gas have negligible forces therefore the particles are far apart and they are more likely to take up more space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Explain why the total positive charge in an atom of an element is always the same

A

Protons gives the nucleus a positive charge and the number of protons of every atom of the same element is the same

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Explain how a cavity wall reduces unwanted energy transfers

A

Cavity wall has two or more layers therefore it has a low thermal conductivity so the energy transferred by conduction is reduced

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Explain the energy stores of a boiler that has a fuel cold water and a hot exhaust gas

A

Chemical energy store of the fuel reduces and energy transferred to the thermal energy store of the water and the air heating up the surroundings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Explain how a reading on a circuit of ammeters and voltmeters changes as environmental conditions change on a circuit containing an LDR

A

Resistance of the LDR changes when the light intensity changes. As light intensity Increases the resistance of the LDR decreases therefore the overall resistance in the circuit decreases.
This means that the current reading on the ammeter will increase as the overall current increases in the circuit. And the potential difference across the LDR will therefore decrease so the reading on the voltmeter will also decrease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How should a student change a circuit to give negative values for current and pd

A

Reverse the connections to the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

The difference between direct and alternating potential difference

A

Direct potential difference is always in the same direction however alternating potential difference changes direction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Explain why it is better to use a cable with do you know resistance when connecting to a car

A

No resistance means high currents therefore the battery of the car charges faster

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

A student increases the temperature of a thermistor explain how the current in the thermostat changed

A

Current increased as resistance decreased

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Switch closes in the circuit containing a lamp how will the potential difference across the lamp change after the switch is closed

A

Potential difference across the lamp will increase as the current will increase because the circuit is complete

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Explain why the temperature heating element increases in a kettle when it is connected to the mains supply

A

Electrons collide with particles in the heating element which increases the thermal energy of the particles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Explain Y on a graph the time taken for kettle to switch off does not go through the origin

A

Because the castle took time to heat up

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why is it difficult to detect gamma radiation

A

Gamma radiation can pass through any detector

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Explain why a count rate detecting the activity of a radioactive substance is less than its actual activity

A

Radiation spreads in all directions and only some of the radiation that passes through passes through the Geiger-Müller tube is detected

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Explain when handling a radioactive substance a teacher stood as far away as possible

A

So they reduce irradiation from the radioactive source as it eradication increases risk of cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Why would it be safe person to touch a metal case when the live wire has touched the case

A

The current flow through the Earth wire as the resistance of the Earth wire is lower than the resistance of the person

19
Q

The temperature of water stays constant even though it is continued to be heated why

A

Energy is dissipated to the surroundings at the same rate that energy is transferred to the water therefore it cannot increase in temperature

20
Q

What is the motion of the particles in solid ice cream

A

They vibrate about in fixed positions

21
Q

When a liquid is called and frozen what happens to the kinetic and potential energy of the particles

A

Both decrease

22
Q

Explain the property a liquid coolant should have

A

A high specific heat capacity so it can absorb more energy with only a small temperature decrease

23
Q

ANB are both radioactive sources source a has a longer half life than B what does this mean

A

The nuclei in source A are more stabler

24
Q

Explain why a kangaroo can jump higher as speed increases

A

Because the max extension increases therefore elastic potential energy also increases this is transferred to the gravitational potential energy

25
Q

Explain why spark detector cannot detect beta radiation as a spark detector works by alpha particles ionising atoms

A

Bator radiation is weekly ionising

26
Q

Compare the reading of an ammenter on a circuit with a resistor to a circuit with a resistor and another resistor added in parallel

A

The reading on the parallel circuit would be twice the reading on the normal circuit

27
Q

What name is given to the energy needed to change the state of a liquid

A

Specific latent heat of fusion

28
Q

Explain why a company that claims they have an efficiency of 400% for a heat pump is not correct

A

Efficiency must be lower than 100% as energy dissipate into the surroundings

29
Q

What is the function of a fuse

A

L protects electrical device if current is greater than value of fuse the fuse will melt and break the circuit

30
Q

What is the function of a fuse

A

L protects electrical device if current is greater than value of fuse the fuse will melt and break the circuit

31
Q

What are the properties of a radioactive source for a medical equipment

A

There should be a short half-life there should also be so there is less damage to cells a low ionising power

32
Q

How does increasing the resistance in a circuit affect the brightness of a lamp

A

Increasing resistance will decrease current therefore the lamp will be dimmer

33
Q

Why was having a more efficient motor increase the speed of a car

A

A lower proportion of wasted energy therefore there is a higher proportion of energy that is converted into kinetic energy

34
Q

What is gamma radiation

A

Electromagnetic radiation from the nucleus

35
Q

Why is gamma emitters used for x-rays

A

Gamma radiation is the most penetrating therefore most of the radiation emitted will leave the body and therefore it can be easily detected outside the body

36
Q

What is the meaning for the term half life

A

The time taken for the number of nuclei of the isotope in a sample to half

37
Q

Describe the hazard course of a radioactive substance that has a short half life

A

Initially there will be a high hazard however the level of hazard will drop quickly due to the short half life

38
Q

Why is a radiated equipment not hazardous

A

They do not become radioactive

39
Q

How may the electrons distance from the nucleus increase or decrease

A

The distance will increase when they absorb electromagnetic radiation and the distance will decrease when they emit electromagnetic radiation

40
Q

Explain and compare two different types of radioactive decay causes transmutation which is the process of an element changing into another

A

Beta decay
Atomic number will increase by one when a neutron decays into a proton
Alpha decay
Atomic number will decrease by two when an alpha particle is emitted from the nucleus
Both change the number of protons in nucleus

41
Q

Explain why a value for specific heat capacity of water is greater than predicted value

A

Some of the energy supplied will not be used to raise the temperature of water

42
Q

Why is heating a gas increases the speed of gas particles

A

will increase the temperature of the gas particles and temperature is proportional to kinetic energy and when kinetic energy increases speed increases

43
Q

Explain why mass of Geseous water with the same temperature of a mass of liquid water has more energy

A

Gassiest water requires more energy as it is needed to change the state of water and break the bonds

Physics (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions