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Must Practice Questions for CBSE Physics CLASS 12: Solved

We will publish here the portions one cannot afford to miss while preparing for the CBSE class 12  Physics Examination

The Chapters will be posted below. On Clicking the name of the chapter a new page will open. On that page there will be a set of collected questions. On clicking the questions, the complete solution to the questions will open.

Please note that this system is under preparation. We hope to complete this within a month. The link will be activated only after completing the project.

  1. ELECTROSTATICS
  2. CURRENT ELECTRICITY
  3. MAGNETIC EFFECTS OF CURRENT
  4. ELECTROMAGNETIC INDUCTION
  5. ALTERNATING CURRENT
  6. ELECTROMAGNETIC WAVES
  7. OPTICS
  8. DUAL NATURE OF MATTER AND RADIATION
  9. ATOMS AND NUCLEI
  10. ELECTRONIC DEVICES
  11. COMMUNICATION SYSTEMS

 

1 comment - What do you think?  Posted by admin - September 30, 2011 at 6:15 pm

Categories: CBSE Physics, Downloads, Model Question Papers, Question Bank   Tags: , , , , , , , , , , , , , , , , , , , ,

Why moon has no atmosphere?

The escape velocity (the minimum velocity with which a body is to be projected so as to escape from the gravitational pull) on the surface of moon is very much less, less than the RMS velocity (Root Mean Square velocity) of the molecules of gas at the surface temperature of moon. Therefore the molecules will escape and therefore moon cannot hold an atmosphere.

The expression for escape velocity is √2gR

The value of escape velocity on earth is 11200 m/s

The value of escape velocity on moon is 2400 m/s (approximately)

The moon’s surface temperature cycles between −155°C and 100° C (−247° and 212° Fahrenheit). As temperature increases the speed of molecules become more than the escape velocity.

However, moon has an extremely thin atmosphere.

Be the first to comment - What do you think?  Posted by admin - January 14, 2012 at 7:35 pm

Categories: CBSE Physics   Tags:

is all physics which we had studied in class 11 and 12 are correct?

Is all physics which we had studied in class 11 and 12 are correct or … ?

Answer:

I would like to quote just one thing, “Science tells the first word of everything and the last word of nothing”

What we learnt yesterday might have changed today and may change in future. We have to adapt ourselves to the new findings, discoveries and inventions.

Further, What we learn in class XI and XII is up to that level and we when we go to higher levels, we learn things more deeply and many things will be dealt differently.

Be the first to comment - What do you think?  Posted by admin - November 14, 2011 at 2:22 pm

Categories: General, Solved Problems   Tags:

Class IX Summative Assessment 1 Science Sample Paper

Download Sample Paper for Class IX Science Summative Assessment 1

Class IX Science Summative Assessment 1
IX Science Question Paper Summative Assessment 1

Be the first to comment - What do you think?  Posted by admin - November 8, 2011 at 2:48 pm

Categories: CBSE Physics   Tags:

Physical World and Measurement

Download a simple test paper from Class XI Physics.

Topic – Physical World and Measurement

Download Here Test on Physical World and Measurement

Be the first to comment - What do you think?  Posted by admin - October 30, 2011 at 3:05 pm

Categories: CBSE Physics   Tags:

Work, Power, Energy & Human Powered Aircraft

Human-powered aircraft require a pilot to pedal, as in a bicycle, and produce a
sustained power output of about 0.30 hp.

The Gossamer Albatross flew across the English Channel on June 12, 1979, in 2h 49 min.

(a) How much energy did the pilot expend during the flight?

(b) How many Snickers candy bars (280 Cal per bar) would the pilot have to consume to be “fueled up” for the flight?

[Note: The nutritional calorie, 1Cal, is equivalent to 1000 calories (1000 cal) as defined in physics. In addition, the conversion factor between calories and joules is as follows: 1Cal = 1000 cal = 1 kcal = 4186 J. ]

Be the first to comment - What do you think?  Posted by admin - October 14, 2011 at 5:41 am

Categories: Mechanics   Tags: , , ,

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