Q. The half-life of tritium is $12.5$ years. What mass of tritium of initial mass $64$mg will remain undecayed after $50$ years?

Q. In a CE amplifier, the input ac signal to be amplified is applied across.

Q. If $A=1$ and $B=0$, then in terms of Boolean algebra, $A+\overline{B}=$?

Q. The density of an electron-hole pair in a pure germanium is $3\times {10}^{16}$ $m^{-3}$ at room temperature. On doping with aluminium, the hole density increases to $4.5\times {10}^{22}{m}^{-3}$. Now the electron density (in $m^{-3}$) in doped germanium will be?

Q. A space station is at a height equal to the radius of the Earth. If ${}^{\prime }{v}_E^{\prime }$ is the escape velocity on the surface of the Earth, the same on the space station is __________ times $v_E$.

Q. A particle shows distance-times curve as shown in the figure. The maximum instantaneous velocity of the particle is around the point.

Q. Which of the following graphs correctly represents the variation of 'g' on the Earth?

Q. A cup of tea cools from ${65.5}^{o}C$ to ${62.5}^o$C in $1$ minute in a room at ${22.5}^o$C. How long will it take to cool from ${46.5}^o$C to ${40.5}^o$C in the same room?

Q. The dimensions of the ratio of magnetic flux $\left(\varphi \right)$ and permeability $\left(\mu \right)$ are?

Q. A mass 'm' on the surface of the Earth is shifted to a target equal to the radius of the Earth. If 'R' is the radius and 'M' is the mass of the Earth, then work done in this process is?

Q. First overtone frequency of a closed pipe of length ${}^{\prime }{l}_1^{\prime }$ is equal to the $2^{nd}$ harmonic frequency of an open pipe of length ${}^{\prime }{l}_2^{\prime }$. The ratio $\frac{l_1}{l_2}=?$

Q. The resistance $R=\frac{V}{I}$ where $V=(100\pm 5)V$ and $I=(10\pm 0.2)A$. The percentage error in R is?

Q. A block rests on a rough inclined plane making an angle of ${30}^o$ with the horizontal. The coefficient of static friction between the block and the plane is $0.8$. If the frictional force on the block is $10$N, the same of the block is $(g=10m{s}^{-2})$.

Q. Two particles of masses $m_1$ and $m_2$ have equal kinetic energies. The ratio of their momenta is?

Q. The pressure at the bottom of a liquid tank is not proportional to the?

Q. A Carnot engine takes $300$ calories of heat from a source at $500$K and rejects $150$ calories of heat to the sink. The temperature of the sink is?

Q. Pressure of an ideal gas is increased by keeping temperature constant. The kinetic energy of molecules.

Q. A man weighing $60$ kg is in a lift moving down with an acceleration of $1.8m{s}^{-2}$. The force exerted by the floor on him is?

Q. Moment of inertia of a body about two perpendicular axes X and Y in the plane of lamina are $20$ kg $m^2$ and $25$ kg $m^2$ respectively. Its amount of inertia about an axis perpendicular to the plane of the lamina and passing through the point of intersection of X and Y axes is?

Q. Two wires A and B are stretched by the same load. If the area of cross-section of wire 'A' is double that of 'B', then the stress of 'B' is?

Q. The magnitude of point charge due to which the electric field $30$cm away has the magnitude $2$ $N{C}^{-1}$ will be?

Q. A mass of $1$ kg carrying a charge of $2$C is accelerated through a potential of $1$V. The velocity acquired by it is?

Q. The force of repulsion between two identical positive charges when kept with a separation 'r' in air is 'F'. Half the gap between the two charges is filled by a dielectric slab of dielectric constant $=4$. Then the new force of repulsion between those two charges becomes :

Q. For the arrangement if capacitors as shown in the circuit, the effective capacitance between the points A and B is? (capacitance of each capacitor is $4$ $\mu F$)

Q. The work done to move a charge on an equipotential surface is?

Q. Two capacitors of $3$ $\mu F$ and $6$ $\mu F$ are connected in series and a potential difference of $900$V is applied across the combination. They are then disconnected and reconnected in parallel. The potential difference across the combination is?

Q. Ohm's Law is applicable to?

Q. If the last band on the carbon resistor is absent, then the tolerance is?

Q. The effective resistance between P and Q for the following network is?

Q. Five identical resistors each of resistance $R=1500$ $\Omega$ are connected to a $300$V battery as shown in the circuit. The reading of the ideal ammeter A is?