Home » 2011 » June » 17

# Daily Archives: June 17, 2011

## Learn Integral Calculus from Scratch

“Where can I learn integration fundamentals”

Just find below one of the best choice for you.

http://www.intmath.com/integration/integration-intro.php

Visit http://www.intmath.com/ for learning the fundamentals of Mathematics

## IIT JEE Physics Syllabus

“Can you tell me the IIT Physics Syllabus and how I should proceed to crack competitive exams, assuming that I am starting fro square one ?”

The IIT JEE Syllabus for Physics is available at http://jee.iitd.ac.in/physics.php

For preparation, the most important books you must study is the NCERT Physics for class XI and XII. Don’t get misguided by someone saying that the NCERT books are not worthy. Almost all the entrance examinations are depending on NCERT syllabus and books to set the standard. The NCERT text book has evolved as a result of strenuous effort of a group of hundreds of teachers from different parts of India and has been revised and updated after consultation and review workshop including teachers from every state. So, it is better to depend on it.

If you have mastered the book and can solve each and every exercise and additional exercise from the NCERT text book, then be glad that you have reached the level expected of you.

The next book you should take for reference is Fundamentals of Physics by  Resnick and Hallidey. (This is the book many of the teachers and authors used to follow before the present revised edition of NCERT text book)

While preparing for IIT or any other competitive exams, it is important to understand the concept basically rather than to practice a large number of numerical problems.

A Chinese proverb says:

“Don’t give fish to a hungry man, teach him how to fish. He will not be hungry again!”

So, our aim is to practice the tactics and methodology with a strong foundation of the subject so that we can solve any type of conceptual or numerical problem.

Dare ask doubts to your teachers. (If you don’t dare, just post them here at www.askphysics.com ). Think and analyse facts yourselves and never depend on mere rot learning. Doubts pop up when you start thinking on what you learn. What you learn must be a part of your brain and life.

Wish you good luck

## Projectile motion on an inclined plane

“Can you tell me about projectile motion on an inclined plane?”

Dear Sourav,

The question is already discussed in detail in the following sites. Please go through them. If you still have doubts, I can explain them in simpler terms.

1. http://www.goiit.com/posts/list/mechanics-projectile-motion-in-inclined-plane-263.htm
2. http://cnx.org/content/m14614/latest/

## Mass of Proton

“how can we say that charge and mass of a proton has a constant value if it depends on the nature of the gas taken”

Answer: The mass of proton does not depend on the nature of gas or material.

## Factors affecting frequency of sound produced by a stretched string

Study how the frequency of sound produced will change in each case with the following strings of length 15cms when the strings are tied between  2 ends-

• aluminium string
• copper string
• cotton string
• metallic string
• jute string

Also study how the pitch changes when the strings are made taught and loose. Study how the frequency of sound changes with thickness of the following strings

• cotton strings
• copper strings

This seems to be a homework question or a project question. Therefore I am not giving a detailed answer so as not to tamper the basic aim of assigning a project.

The frequency of sound produced by a stretched string depends on the following factors:

1. the length of the string
2. the linear mass density (i.e; the mass per unit length) of the string
3. the tension in the string

When you are using strings of different materials, the factor which changes is the mass per unit length and the same is true when you are changing the thickness.

When you make the string more taut, the tension increases and vice versa.

The question is given for a constant length. Therefore the case of effect of changing length does not come into picture.

The formula showing the relationship is $\large \fn_jvn f=\frac{1}{2L}\sqrt{\frac{T}{m}}$

it is evident from the formula that the frequency of sound is

• inversely proportional to the  length
• directly proportional to the square root of tension in the string and
• inversely proportional to the square root of linear density of the string.

on proper substitution, the formula can be recast as

$\large \fn_jvn f=\frac{1}{Ld}\sqrt{\frac{T}{\pi \rho }}$

and this will be more convenient for you to answer the questions.

I recommend that you try to explore by actually performing the experiments.

### Hits so far @ AskPhysics

• 2,227,489 hits

### CBSE Exam Count Down

AISSCE / AISSE 2020February 26, 2020
Board Exams for the core subjects of CBSE may start from 26 February (Class X) and 27 February (Class XII)