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Which of the following graph represents the variation of resistivity ($\rho$) with temperature (T) for copper?
Two bodies of mass $4\text{ kg}$ and $6\text{ kg}$ are tied to the ends of a massless string. The string passes over a pulley which is frictionless (see figure). The acceleration of the system in terms of acceleration due to gravity (g) is :
A charged particle having drift velocity of $7.5 \times 10^{-4} \text{ m s}^{-1}$ in an electric field of $3 \times 10^{-10} \text{ Vm}^{-1}$, has a mobility in $\text{m}^2 \text{ V}^{-1} \text{ s}^{-1}$ of :
Which of the following is a correct sequence of steps in a PCR (Polymerase Chain Reaction)?
For a plane electromagnetic wave propagating in $x$-direction, which one of the following combination gives the correct possible directions for electric field ($E$) and magnetic field ($B$) respectively?
The velocity of a small ball of mass $M$ and density $d$, when dropped in a container filled with glycerine becomes constant after some time. If the density of glycerine is $\frac{d}{2}$, then the viscous force acting on the ball will be
The electron concentration in an $n$-type semiconductor is the same as hole concentration in a $p$-type semiconductor. An external field (electric) is applied across each of them. Compare the currents in them.
Consider the following statements (A) and (B) and identify the correct answer. (A) A zener diode is connected in reverse bias, when used as a voltage regulator. (B) The potential barrier of p-n junction lies between 0.1 V to 0.3 V.
The fruit fly has 8 chromosomes (2n) in each cell. During interphase of Mitosis if the number of chromosomes at $G_1$ phase is 8, what would be the number of chromosomes after S phase?
Two conducting circular loops of radii $R_1$ and $R_2$ are placed in the same plane with their centres coinciding. If $R_1 >> R_2$, the mutual inductance $M$ between them will be directly proportional to
A capacitor of capacitance 'C', is connected across an ac source of voltage $V$, given by $V = V_0 \sin \omega t$. The displacement current between the plates of the capacitor, would then be given by
Polar molecules are the molecules
Two charged spherical conductors of radius $R_1$ and $R_2$ are connected by a wire. Then the ratio of surface charge densities of the spheres ($\sigma_1/\sigma_2$) is
Water falls from a height of $60\text{ m}$ at the rate of $15\text{ kg/s}$ to operate a turbine. The losses due to frictional force are $10\%$ of the input energy. How much power is generated by the turbine? ($g = 10\text{ m/s}^2$)
For the given circuit, the input digital signals are applied at the terminals $A$, $B$ and $C$. What would be the output at the terminal $y$?
A dipole is placed in an electric field as shown. In which direction will it move?
The number of photons per second on an average emitted by the source of monochromatic light of wavelength $600\text{ nm}$, when it delivers the power of $3.3 \times 10^{-3}\text{ watt}$ will be ($h = 6.6 \times 10^{-34}\text{ J s}$)
An infinitely long straight conductor carries a current of $5\text{ A}$ as shown. An electron is moving with a speed of $10^5\text{ m/s}$ parallel to the conductor. The perpendicular distance between the electron and the conductor is $20\text{ cm}$ at an instant. Calculate the magnitude of the force experienced by the electron at that instant.
A particle of mass '$m$' is projected with a velocity $v = kv_e$ ($k < 1$) from the surface of the earth. ($v_e$ = escape velocity). The maximum height above the surface reached by the particle is
An emf is generated by an ac generator having 100 turn coil, of loop area 1 m². The coil rotates at a speed of one revolution per second and placed in a uniform magnetic field of 0.05 T perpendicular to the axis of rotation of the coil. The maximum value of emf is: