Biology; Chemistry; Physics: Post your doubts here!

[Lilly2318]

Help me in part b) the ans for a) is 40

 

[asadalam]

Help me in part b) the ans for a) is 40

Time =25/60=0.416 Hours
Cost=9.6x0.416x21=84 cents

 

[Lilly2318]

Help me in part b) the ans for a) is 40

Ans is 84 cents

 

[Lilly2318]

Time =25/60=0.416 Hours
Cost=9.6x0.416x21=84 cents

did u use ratio in second part?

 

[asadalam]

did u use rati in second part?

No.I used the power.Often if the question is linked it would be followed by letters like if rating was involved it would be a)iii) instead of b).A new part indicates a whole new side usually.This hint can help you to find out what to include in the answers.

 

[Mahnoorfatima]

There's this question of o/n 2010 paper 22 qs 5of oscilloscope .. Can anybody check it out please? I don't know how to post the link on my iPad.. My answer's 1.25 whereas in ms it's 1250. Anyone ? Please?

 

[Awesome12]

There's this question of o/n 2010 paper 22 qs 5of oscilloscope .. Can anybody check it out please? I don't know how to post the link on my iPad.. My answer's 1.25 whereas in ms it's 1250. Anyone ? Please?

To post the link, just press and hold the link, it will become highlighted. There will be 2 draggers on each side to extend the copied text, and then just click on copy

 

[DaniyalK]

There's this question of o/n 2010 paper 22 qs 5of oscilloscope .. Can anybody check it out please? I don't know how to post the link on my iPad.. My answer's 1.25 whereas in ms it's 1250. Anyone ? Please?

Time Period = 0.2 * 10^-3 * 4 = 0.0008
Frequency = 1 /0.0008 = 1250 Hz

 

[Mahnoorfatima]

http://papers.xtremepapers.com/CIE/Cambridge International O Level/Physics (5054)/5054_w10_qp_22.pdf
Oh wow! Thanks awesome 12! Okay so I'm talking about qs 5 part a. And the b part. How come the frequency is the same for both of the waves?

 

[faraz shahid]

time shud be converted to seconds to apply it to the formula

 

[Lilly2318]

f is 1/t
1/490.2Xo.oo1

 

[faraz shahid]

http://papers.xtremepapers.com/CIE/Cambridge International O Level/Physics (5054)/5054_w10_qp_22.pdf
Oh wow! Thanks awesome 12! Okay so I'm talking about qs 5 part a. And the b part. How come the frequency is the same for both of the waves?

frequency doesnot change throughout the wave..its one of the major property of a wave.

 

[Mahnoorfatima]

Time Period = 0.2 * 10^-3 * 4 = 0.0008
Frequency = 1 /0.0008 = 1250 Hz

Yeah but why 10^-3???

 

[princess Anu]

.

the first one.....
if you make the image of student Z and X,
then make rays touching corner of mirror from Y (extended behind mirror) this way you get region visible by student Y
the images of X and Z fall in the region so student Y see himself,Z and X SO ANSWER IS 3 THAT IS D
for 2nd one....
the answer is A (i think )
as the voltage is less and more turns in secondary coil increase voltage , rest remains same so A seems right......

Can u show your working on this picture for the first one please

 

[Lilly2318]

http://papers.xtremepapers.com/CIE/Cambridge International O Level/Physics (5054)/5054_w10_qp_22.pdf
Oh wow! Thanks awesome 12! Okay so I'm talking about qs 5 part a. And the b part. How come the frequency is the same for both of the waves?

f is 1/t
1/490.2Xo.oo1

 

[faraz shahid]

Yeah but why 10^-3???

to covert it into seconds to apply it to the formula..

 

[DaniyalK]

Yeah but why 10^-3???

Because it's milli second. And in part b, the pattern of both waves repeat after every 4 squares.

 

[kirann]

HOW ITS DONE?

 

[DaniyalK]

HOW ITS DONE?View attachment 42822

Find the number of half lives it will take to get to 90 counts/s then multiply that by the time (2400 years)

 

[faraz shahid]

Every 2400 years the radioactivety is reduced by 1/2. It will take 3 half life cycles for this sample to reach 90.
720/2 = 360, 360/2 = 180, 180/2 = 90.
3 * 2400yrs = 7200yr