6PH05 Physics Unit 5: From Creation To Collapse, June 20

I don't even know any experiments for this module.

What is a standard candle and what are their uses? (This was a 4 mark question, I wasn't in college when we covered it and I have no idea)

Reply 141

gkweic

Original post by freakynerdlol

What are 'confinement' problems? I have seen it several times in mark schemes

Posted from TSR Mobile

its referring to the high temperatures 5000k< (i think that right temp), needed for a successful fusion reaction to start, obviously with temperatures such as these only incredible durbable materials can withstand the temperature and so it is a problem trying to confine the reaction

Reply 142

andyl95

Could somehow please kindly explain this question to me?
I really don't understand it whatsoever even though I know it's to do with resonance since the amplitude of the oscillations would increase.

(Jan 2012, Question 14)

Reply 143

opengeek

5

LAST EXAM TOMORROW :biggrin:

WOOOOP WOOOOP :dancing:

Reply 144

andyl95

Original post by Appeal to reason

I don't even know any experiments for this module.

What is a standard candle and what are their uses? (This was a 4 mark question, I wasn't in college when we covered it and I have no idea)

Standard candles are objects with known luminosity.
If the intensity of a star were measured and its luminosity were determined (from standard candles), the inverse square law can be used to determine the distance from Earth

Reply 145

h2shin

9

Original post by andyl95

Could somehow please kindly explain this question to me?
I really don't understand it whatsoever even though I know it's to do with resonance since the amplitude of the oscillations would increase.

(Jan 2012, Question 14)

This question is about resonance.
The tuning fork forces the box to oscillate at a certain frequency and due to the fact that the fork and the box have similar natural frequency (we assume this) there is an efficient transfer of energy and the box undergoes resonance and oscillates. As the box has a larger surface area than the tuning fork, it disturbs / causes more air molecules to oscillate, resulting In a higher amplitude and this a louder sound. But because the box is absorbing energy from the fork it is essentially dampening the forks oscillation, which causes the forks amplitude to decreas more rapidly than if only the air was dampening the forks oscillations, which means the sound lasts for a shorter amount of time.

Reply 146

AshleyP95

Original post by freakynerdlol

What are 'confinement' problems? I have seen it several times in mark schemes

Posted from TSR Mobile

Yeah I've seen that lots too. It's to do with the high temperature of nuclear fusion right?
I think confinement problems refers to the fact that it would be hard to keep the high temperature within the container without damaging other stuff around it like the rest of the lab, city, world etc.

Reply 147

dendodge

9

Original post by freakynerdlol

What are 'confinement' problems? I have seen it several times in mark schemes

Posted from TSR Mobile

It means it's really really hot and there's a lot of pressure, so we can't build anything strong enough to contain it without exploding all over everybody and turning half the country into a barren wasteland.

Reply 148

dendodge

9

Original post by andyl95

Could somehow please kindly explain this question to me?
I really don't understand it whatsoever even though I know it's to do with resonance since the amplitude of the oscillations would increase.

(Jan 2012, Question 14)

Natural frequency of tuning fork ~= Natural frequency of sounding box.
Tuning fork forces sounding box to resonate, therefore resonance occurs and the sound produced has a larger amplitude.

Energy is transferred from the fork to the box, which in turn transfers a lot of energy into the air, by making lots of air molecules vibrate due to its large surface area. This means the oscillations are heavily damped.

Reply 149

andyl95

Original post by dendodge

Natural frequency of tuning fork ~= Natural frequency of sounding box.
Tuning fork forces sounding box to resonate, therefore resonance occurs and the sound produced has a larger amplitude.

Energy is transferred from the fork to the box, which in turn transfers a lot of energy into the air, by making lots of air molecules vibrate due to its large surface area. This means the oscillations are heavily damped.

True, but I thought that's resonance though because the air molecules are vibrating at an increased amplitude?

Reply 150

dendodge

9

Original post by andyl95

True, but I thought that's resonance though because the air molecules are vibrating at an increased amplitude?

Yeah, that's why we hear the sound, but the energy is used to make the sound, and therefore no longer in the system, which means the oscillations get smaller.

Reply 151

Zzzyax

OP

2

Original post by freakynerdlol

What are 'confinement' problems? I have seen it several times in mark schemes

Posted from TSR Mobile

i will explain it in a way everyone can understand

If you were trying to start nuclear fusion here on earth, you need high temperature to overcome the electrostatic repulsion between nuclei (not nucleons) you also need high pressure and density to get a high collision rate. great. this all requires very high energy. so containment problems are the problem of containing the materials that will fuse, being the high temp/pressure required, ie a normal nuclear reactor would simply melt, and any contact with the walls of a container would lose heat, lose energy.

Reply 152

andyl95

Original post by dendodge

Yeah, that's why we hear the sound, but the energy is used to make the sound, and therefore no longer in the system, which means the oscillations get smaller.

Ah yeah that makes sense now thank-you!

Got another question, I'm asked to explain what causes the Moon to orbit the Earth in a circular path and what determines the radius of this path?

I got the 1st bit as the weight of the moon acts as the centripetal force...but I don't know what determines the path? :frown:

Reply 153

rrw12

Any revision guide that i can use?

Reply 154

iwantopas19

I just hope questions ''general knowledge'' is not tested on this paper

Reply 155

iwantopas19

how do we measure distance using standard candle ??

Reply 156

Effort

Wow, I thought the exam was day after tomorrow so now I am cramming like crazy wahaha...Hopefully paper has nothing too tricky.

Reply 157

AT95

Can someone tell ne how to do june10 q4?? Please?

Posted from TSR Mobile

Reply 158

Farhan_moin

1 hr to go ....best of luck every 1

Reply 159

Farhan_moin

Original post by AT95

Can someone tell ne how to do june10 q4?? Please?

Posted from TSR Mobile

Its like this......mass of oxygen is 16 times more so to keep random KE same <c2> must be 4 times less (as indirect relation squared) because they both have same temp .now use normal algebra its B

6PH05 Physics Unit 5: From Creation To Collapse, June 20

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you