1
AIPMT 2010 Prelims
MCQ (Single Correct Answer)
+4
-1
A lens having focal length f and aperture of diameter d forms an image of intensity I. Aperture of diameter $${d \over 2}$$ in central region of lens is covered by a black paper. Focal length of lens and intensity of image now will be respectively
A
$$f\,$$ and $${I \over 4}$$
B
$${{3f} \over 4}$$ and $${I \over 2}$$
C
$$f$$ and $${{3I} \over 4}$$
D
$${f \over 2}$$ and $${I \over 2}$$
2
AIPMT 2010 Prelims
MCQ (Single Correct Answer)
+4
-1
Consider the following two statements.
(A)  Kirchoff's junction law follows from the conservation of charge.
(B)  Kirchhoff's loop law follows from the conservation of energy.

Which of the following is correct?
A
Both (A) and (B) are wrong
B
(A) is correct and (B) is wrong
C
(A) is wrong and (B) is correct
D
Both (A) and (B) are correct
3
AIPMT 2010 Prelims
MCQ (Single Correct Answer)
+4
-1
A beam of cathode rays is subjected to crossed electric (E) and magnetic fields (B). The fields are adjusted such that the beam is not deflected. The specific charge of the cathode rays is given by

(Where V is the potential difference between cathode and anode)
A
$${{{B^2}} \over {2V{E^2}}}$$
B
$${{2V{B^2}} \over {{E^2}}}$$
C
$${{2V{E^2}} \over {{B^2}}}$$
D
$${{{E^2}} \over {2V{B^2}}}$$
4
AIPMT 2010 Prelims
MCQ (Single Correct Answer)
+4
-1
The potential difference that must be applied to stop the fastest photoelectrons emitted by a nickel surface, having work functions 5.01 eV, when ultraviolet light of 200 nm falls on it, must be
A
2.4 V
B
$$-$$ 1.2 V
C
$$-$$ 2.4 V
D
1.2 V
EXAM MAP