Biology; Chemistry; Physics: Post your doubts here!

[ashiqbal]

thanks a lot ashiqbal and a.abid . U guys will definitely get a stars!

lets hope so!

 

[Muhammad Zain Qasmi]

Well it should be 1/(0.2)*4 right ? But the mark schemes shows 1250 Hz as the actual answer. How ?

 

[Dashing Cancerian]

Here are a few questions that i came across:

Q1- Why is the stem of a thermometer often oval in cross section?

Q2-Which of the following statements about alpha particles is not true?
A. they can be deflected by magnetic field
B. they can be deflected by electric fiel
C. they can be detected by spark counter
D. they are radioactive
(first tell me ur answer then i'll tell the correct answer )

Q3-State 2 precautions u should take wen using vernier calipers. (except zero error)

Q4-State 2 precautions u shud take wen using a micrometer screw guage (except zero error)

Please answer asap!!

Q1- it magnifies the reading

Q3- the position of eye should be perpendicular to the reading.... so the parallax error chances may be reduced...

rest i dunnnoo,,,...

 

[a.abid]

Well it should be 1/(0.2)*4 right ? But the mark schemes shows 1250 Hz as the actual answer. How ?

Now see.One cycle completes in----->4 div.
So,time taken=4 x 0.20=0.8ms
Now the SI unit for time is SECONDS so 0.8/1000=0.0008s
Now Frequency=1/time interval=1/0.0008=1250Hz

 

[syed1995]

Let's clear this concept once and for all..

The answer is C or D?

 

[Dashing Cancerian]

Let's clear this concept once and for all..

The answer is C or D?

D

 

[beeloooo]

D !!

 

[asd]

Q1- it magnifies the reading

Q3- the position of eye should be perpendicular to the reading.... so the parallax error chances may be reduced...

rest i dunnnoo,,,...

2 is D?

 

[asd]

2 is D?

daredevil DUH!

 

[a.abid]

Let's clear this concept once and for all..

The answer is C or D?

D-this is because 9+9=18 and as the side of the cylinder has more pressure than the Longer side which represents the atmospheric pressure side,so it is ABOVE atmospheric pressure.

 

[Dashing Cancerian]

2 is D?

not studied yet

 

[Muhammad Zain Qasmi]

Now see.One cycle completes in----->4 div.
So,time taken=4 x 0.20=0.8ms
Now the SI unit for time is SECONDS so 0.8/1000=0.0008s
Now Frequency=1/time interval=1/0.0008=1250Hz

oh lawl, by "ms" it meant <millisecond>
Thank u so much

 

[a.abid]

Q1- it magnifies the reading

Q3- the position of eye should be perpendicular to the reading.... so the parallax error chances may be reduced...

rest i dunnnoo,,,...

The answer for 2 is D this is because Alpha particles are NOT radioactive-they r only radiations,its the element that emits these particles called radioactive.

 

[a.abid]

oh lawl, by "ms" it meant <millisecond>
Thank u so much

Np

 

[Dashing Cancerian]

The answer for 2 is D this is because Alpha particles are NOT radioactive-they r only radiations,its the element that emits these particles called radioactive.

i dnt even know the basics of ths chap

 

[a.abid]

2 is D?

yes.

 

[a.abid]

i dnt even know the basics of ths chap

LOL okay but thats the correct answer

 

[Dashing Cancerian]

LOL okay but thats the correct answer

i never asked for it...

 

[bogus]

I have my physics paper day after tomorrow so I would be glad if someone can these problems

1. Describe simple experiments to show refraction of sound waves.
2. Describe the factors which influence the quality (timbre) of sound waves and how these factors may be demonstrated.
3. Use of ultra sound in quality control.
4. Discuss the environmental and cost implications of underground power transmission compared to overhead lines.
5. State the meaning of the terms processor, output device and feedback.
6. Describe the use of a bistable circuit.
7. Describe the use of a astable circuit. Describe how the frequency of an astable circuit is related to the values of the resistive and capacitive components.
8. Describe with the aid of a block diagram one type of fission reactor for the use in a power station.

All these topics are listed in the syllabus.
Waiting for someone to reply.

Thankyou

 

[ayeshaK]

I have my physics paper day after tomorrow so I would be glad if someone can these problems

1. Describe simple experiments to show refraction of sound waves.
2. Describe the factors which influence the quality (timbre) of sound waves and how these factors may be demonstrated.
3. Use of ultra sound in quality control.
4. Discuss the environmental and cost implications of underground power transmission compared to overhead lines.
5. State the meaning of the terms processor, output device and feedback.
6. Describe the use of a bistable circuit.
7. Describe the use of a astable circuit. Describe how the frequency of an astable circuit is related to the values of the resistive and capacitive components.
8. Describe with the aid of a block diagram one type of fission reactor for the use in a power station.

All these topics are listed in the syllabus.
Waiting for someone to reply.

Thankyou

Physics is tmwrw !!