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# Quantum Phenomena watch

1. https://00c07169b8f01b5b433281e611ee...%20Physics.pdf

question 4b part 3 how do i do it? i know i've done something wrong since the answer i got for 4b part 4 was the wavelength of light given in the question >.>
2. (Original post by thefatone)
https://00c07169b8f01b5b433281e611ee...%20Physics.pdf

question 4b part 3 how do i do it? i know i've done something wrong since the answer i got for 4b part 4 was the wavelength of light given in the question >.>
we know that max kinetic energy = hf - phi.

Kinetic energy is 1/2 mv^2 so, kinetic energy/(1/2)m should equal v^2

Then square root the answer. Is this correct?
3. (Original post by Kyx)
we know that max kinetic energy = hf - phi.

Kinetic energy is 1/2 mv^2 so, kinetic energy/(1/2)m should equal v^2

Then square root the answer. Is this correct?
well ffs then i didn't even know to use that -.-

i'll tag you a few more times when i get stuck
4. (Original post by thefatone)
well ffs then i didn't even know to use that -.-
5. (Original post by Kyx)
what about q5 part 2? i don't understand
6. (Original post by thefatone)
what about q5 part 2? i don't understand
Using the resistivity formula, make R the subject.

Then it would be easier to see the relationship
7. (Original post by Kyx)
Using the resistivity formula, make R the subject.

Then it would be easier to see the relationship
so i saw radius is halved and length is multiplied by 4

so i got this

then i said well this means that
8. (Original post by thefatone)
so i saw radius is halved and length is multiplied by 4

so i got this

then i said well this means that
No. In area, the radius is squared. It is 1/4 divided by 4, which makes it 16 methinks.
9. (Original post by Kyx)
No. In area, the radius is squared. It is 1/4 divided by 4, which makes it 16 methinks.
oh i see so it's 1/4 which mean the bottom is also multiplied by 4 so that's a total of 16 times .....

wait why does resistance increase? why doesn't it ... NVM

thanks for the help i'll probably tag you in again in a minute
10. (Original post by thefatone)
oh i see so it's 1/4 which mean the bottom is also multiplied by 4 so that's a total of 16 times .....

wait why does resistance increase? why doesn't it ... NVM

thanks for the help i'll probably tag you in again in a minute
Rearrange to make R the subject

You get 4 divided by 1/4 which equals 16
11. (Original post by Kyx)
Rearrange to make R the subject

You get 4 divided by 1/4 which equals 16
yup thanks i got it ^-^

can you help on 5b i have no idea where to start
12. (Original post by thefatone)
yup thanks i got it ^-^

can you help on 5b i have no idea where to start
First of all, what equipment would you need?

Then, how would you set it up (parallel, series)?

What measurements you would make?

How you would use the measurements to find the resistivity?

How you can make these measurements as precise as possible?
13. (Original post by Kyx)
First of all, what equipment would you need?

Then, how would you set it up (parallel, series)?

What measurements you would make?

How you would use the measurements to find the resistivity?

How you can make these measurements as precise as possible?
1. obviously voltmeter ammeter putty wires cells ruler can't think of anything else
2. no idea maybe series?
3. taking down values of V and I when i connect the circuit up. radius of putty, length of putty

4. [latex]R=\dfrac{V}{I}\ and\ sub in values into \rho= \dfrac{RA}{L}
5. use a measuring tool with smallest increment?
14. (Original post by thefatone)
1. obviously voltmeter ammeter putty wires cells ruler can't think of anything else
2. no idea maybe series?
3. taking down values of V and I when i connect the circuit up. radius of putty, length of putty

4. [latex]R=\dfrac{V}{I}\ and\ sub in values into \rho= \dfrac{RA}{L}
5. use a measuring tool with smallest increment?
2. how would you put the voltmeter? How would you put the ammeter?
Spoiler:
Show
Clue: one is series, the other is parallel
15. (Original post by Kyx)
2. how would you put the voltmeter? How would you put the ammeter?
Spoiler:
Show
Clue: one is series, the other is parallel
ah ok so a basic circuit

but wouldn't repeating give me accurate answers not precise ones?
16. (Original post by thefatone)
ah ok so a basic circuit

but wouldn't repeating give me accurate answers not precise ones?
Correct

Glad you saw that
17. (Original post by Kyx)
Correct

Glad you saw that
my teachers especially physics and chem ramble on so much about the difference between accurate an precise is unreal so that's stayed in my head
18. (Original post by thefatone)
my teachers especially physics and chem ramble on so much about the difference between accurate an precise is unreal so that's stayed in my head
Probably for the best
19. (Original post by Kyx)
Probably for the best
yup
20. (Original post by Kyx)
Probably for the best
how would i do question 6a part 2?

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