Wednesday, November 24, 2010

Apply for All India Engineering/Architecture Entrance Examination 2011 (AIEEE 2011)

Application Form and the Information Bulletin in respect of the All India Engineering/Architecture Entrance Examination 2011 (AIEEE 2011) to be conducted on 24-4-2011 will be distributed from 15.12.2010 and will continue till 14.1.2011. Candidates can apply for AIEEE 2011 either on the prescribed Application Form or make application ‘Online’.

Online submission of the application is possible from 23-11-2010 to 14-1-2011 at the website

Visit the site for all details and information updates.

You will find many old AIEEE questions (with solution) on this site. You may search for ‘AIEEE’, using the search box at the top of this page, to access all posts in this context.

Tuesday, November 16, 2010

All India Pre-Medical / Pre-Dental Entrance Examination -2011 (AIPMT 2011)

Central Board of Secondary Education (CBSE), Delhi has invited applications in the prescribed form for All India Pre-Medical / Pre-Dental Entrance Examination -2011 as per the following schedule for admission to 15% of the merit positions for the Medical/Dental Courses of India

1. Preliminary Examination …. 3rd April, 2011 (Sunday) 10 AM to 1 PM

2. Final Examination ………… 15th May, 2011 (Sunday) 10 AM to 1 PM

The Preliminary Examination as well as the Final Examination would be objective type.

Candidate can apply for the All India Pre-Medical/Pre-Dental Entrance Examination either offline or online. Here are the important dates in this regard:

Sale of bulletin : 13-12-2010 to 31-12-2010

Online submission : 15-11-2010 to 31-12-2010

Last date of receipt of

(a) Offline application : 07-1-2011

(b) Online application : 07-1-2011

(Confirmation page)

Visit the site for detailed information.

You will find some old AIPMT questions with solution on this blog. You can access these questions by searching for ‘AIPMT’, making use of the search box provided on this page.

Tuesday, November 09, 2010

IIT JEE 2010 Question (MCQ) on Magnetic Force on Current Carrying Conductors

“I object to violence because when it appears to do good, the good is only temporary; the evil it does is permanent.”

– Mahatma Gandhi

The following question which appeared in IIT JEE 2010 question paper is worth noting:

A thin flexible wire of length L is connected to two adjacent fixed points and carries a current I in the clockwise direction, as shown in the figure.

When the system is put in a uniform magnetic field of strength B going into the plane of the paper, the wire takes the shape of a circle. The tension in the wire is

(a) iBL

(b) iBL /π

(c) iBL /

(d) iBL /

Considering an elemental length dL of the wire, the magnetic force F acting on the element is given by

F = idLB = iRdθB, as is clear from the figure.

The tension T developed in the wire is resolved into rectangular components T sin(dθ/2) and T cos(dθ/2) as indicated in the figure.

The magnetic force F is related to the tension T as

F = iRdθB = 2T sin(dθ/2)

Since is a very small angle, sin(dθ/2) ≈ dθ/2

Therefore, the above equation gives T = iRB

But R = L /

Therefore, T = iBL /

Now, consider the following MCQ which is quite simple contrary to the impression of some of you:

Two straight, infinitely long parallel wires P and Q carry equal currents (I) in opposite directions (fig.). A square loop of side a carrying current i is arranged symmetrically in between the straight wires so that the plane of the loop is in the plane containing the wires P and Q. What is the torque acting on the current loop?

(a) Zero

(b) μ0Iia2/2πd

(c) (μ0Iia2/2π)[1/(d+a)]

(d) (μ0Iia2/2π)[1/d + 1/(d+a)]

(e) (μ0Iia2/2π)[1/d 1/(d+a)]

The resultant magnetic forces acting on the four sides of the current loop act at their centres. The forces on the opposite sides of the loop are oppositely directed as you can easily verify using Fleming’s left hand rule. Since the lines of action of the resultant forces on opposite sides of the loop coincide, there is no lever arm to produce a torque and hence the torque is zero.

Monday, November 01, 2010

Apply for Joint Entrance Examination 2011 (JEE 2011) for Admission to IITs

Notification regarding the Joint Entrance Examination 2011 (JEE 2011) for Admission to IITs has been issued. This Joint Entrance Examination is for admission to the under graduate programmes in the IITs at Bhubaneswar, Bombay, Delhi, Gandhinagar, Guwahati, Hyderabad, Indore, Kanpur, Kharagpur, Madras, Mandi, Patna, Rajasthan, Roorkee and Ropar as well as at IT-BHU Varanasi and ISM Dhanbad.

Important Dates for IIT JEE 2011:

November 01 to December 15, 2010: Online application process
November 12 to December 15, 2010: Sale of Off-line application forms.

Last date for receiving application forms (Off line or printed copy of Online) at IITs: 17:00 hrs, Monday, December 20, 2010

Date of Exam of IIT JEE 2011:

Sunday, April 10, 2011 Paper 1: 09:00 to 12:00 hrs;

Paper 2 : 14:00 to 17:00 hrs

All information regarding online application and offline application and other important details about IIT JEE 2011 can be obtained from the following websites:

IIT Bombay:
IIT Guwahati:
IIT Delhi:
IIT Kharagpur:
IIT Kanpur:
IIT Roorkee:

IIT Madras: