If $C$ is the midpoint of $AB$ and $P$ is any point outside $AB$,then:

When a light of a given wavelength falls on a metallic surface the stopping potential for photoelectrons is $3.2 \ V$. If a second light having wavelength twice of first light is used, the stopping potential drops to $0.7 \ V$. The wavelength of first light is . . . . . . $m$.
$(h = 6.63 \times 10^{-34} \ J.s, e = 1.6 \times 10^{-19} \ C, c = 3 \times 10^8 \ m/s)$

Genetic counsellors can identify heterozygous individuals by

Sertoli cells are regulated by the pituitary hormone known as:

$A$ working transistor with its three legs marked $P, Q$ and $R$ is tested using a multimeter. No conduction is found between $P$ and $Q$. By connecting the common (negative) terminal of the multimeter to $R$ and the other (positive) terminal to $P$ or $Q$,some resistance is seen on the multimeter. Which of the following is true for the transistor?

$A$ stationary horizontal disc is free to rotate about its axis. When a torque is applied on it,its kinetic energy as a function of $\theta$,where $\theta$ is the angle by which it has rotated,is given as $K \theta^2$. If its moment of inertia is $I$,then the angular acceleration of the disc is: