Phy p 41

[Starry_night]

this is sound wave my dear....wat u saying is for light and electromagnetic waves

Yeah, but if I'm remembering correctly, the question said that a radio wave was being modulated, ravio waves belonging to the EM spectrum and travelling at c (3x10^8 ms-1)

 

[Starry_night]

What was the answer for the one where it asked for the effect on emission of electrons if u maintained the intensity of light but increased its frequency? Also which of the given metals would electrons be emitted from?

 

[marz_katy]

What was the answer for the one where it asked for the effect on emission of electrons if u maintained the intensity of light but increased its frequency? Also which of the given metals would electrons be emitted from?

i rote the rate would be same cz it only depnds on intensity..bt ds is rong..actually the rate will be reduced=(

 

[marz_katy]

Yeah, but if I'm remembering correctly, the question said that a radio wave was being modulated, ravio waves belonging to the EM spectrum and travelling at c (3x10^8 ms-1)

im not sure of dat..atleast fr formula will get 1 mark

 

[Starry_night]

i rote the rate would be same cz it only depnds on intensity..bt ds is rong..actually the rate will be reduced=(

I also put that it remains the same. How sure are u that it's wrong?

 

[marz_katy]

I also put that it remains the same. How sure are u that it's wrong?

chk 2011 mj v-1 ques 7 c part two and chck ms an er..ul get it

 

[AdeleintheDeep]

In the nuclear fusion reaction, were we supposed to add all the mass defects and use E= mass defect * c^2 ??

 

[Jaf]

In the nuclear fusion reaction, were we supposed to add all the mass defects and use E= mass defect * c^2 ??

Add...... all the mass defects?! :S
Add the mass of reactants. Subtract mass of product from this. Multiply the answer by the value of u in kg (given in the beginning of the paper). You then multiply this by c^2 (3x10^8)^2 to get the answer in joules. This is the mass defect.

 

[mady666]

What about the xray question? Was the contrast good or bad?

 

[AdeleintheDeep]

good

 

[Jaf]

For the charged sphere, I calculated the voltage of of the particle as well, and I got 300something. And said that it wouldn't reach the sphere.

For the two cylinder one- I also got 356 K, but I don't think it would be that easy... I left that part and did it last.. I mean it was for 3 marks, there's more to it then simply throwing the numbers in the formula.. Idk. :/

Wasn't just throwing... add the volumes, add the moles... get the answer. I also said the two cylinders acted like one. xD