1
AIPMT 2015
MCQ (Single Correct Answer)
+4
-1
Change Language
A photoelectric surface is illuminated successively by monochromatic light of wavelength $$\lambda $$ and $$\lambda/2 $$. If the maximum kinetic energy of the emitted photoelectrons in the second case is 3 times that in the first case, the work function of the surface of the material is
(h = Planck's constant, C = speed of light)
A
$${{2hc} \over \lambda }$$
B
$${{hc} \over {3\lambda }}$$
C
$${{hc} \over {2\lambda }}$$
D
$${{hc} \over \lambda }$$
2
AIPMT 2015
MCQ (Single Correct Answer)
+4
-1
Change Language
In the spectrum of hydrogen, the ratio of the longest wavelength in the Lyman series to the longest wavelength in the Balmer series is
A
$${{27} \over 5}$$
B
$${5 \over {27}}$$
C
$${4 \over 9}$$
D
$${9 \over 4}$$
3
AIPMT 2015
MCQ (Single Correct Answer)
+4
-1
Change Language
Point masses m1 and m2 are placed at the opposite ends of a rigid rod of length L, and negligible mass. The rod is to be set rotating about an axis perpendicular to it. The position of point P on this rod through which the axis should pass so that the work required to set the rod rotating with angular velocity $$\omega $$0 is minimum, is given by

AIPMT 2015 Physics - Rotational Motion Question 80 English
A
$$x = {{{m_2}} \over {{m_1}}}L$$
B
$$x = {{{m_2}L} \over {{m_1} + {m_2}}}$$
C
$$x = {{{m_1}L} \over {{m_1} + {m_2}}}$$
D
$$x = {{{m_1}} \over {{m_2}}}L$$
4
AIPMT 2015
MCQ (Single Correct Answer)
+4
-1
Change Language
On a frictionless surface, a block of mass M moving at speed v collides elastically with another block of same mass M which is initially at rest. After collision the first block moves at an angle $$\theta $$ to its initial direction and has a speed $${v \over 3}.$$ The second block's speed after the collision is
A
$${3 \over {\sqrt 2 }}v$$
B
$${{\sqrt 3 } \over 2}v$$
C
$${{2\sqrt 2 } \over 3}v$$
D
$${3 \over 4}v$$