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The mean free path of electrons in a metal is 4 × 10⁻⁸ m. The electric field which can give on an average 2 eV energy to an electron in the metal will be in a unit of V m⁻¹:
Twenty seven drops of same size are charged at 220 V each. They combine to form a bigger drop. Calculate the potential of the bigger drop:
Dimensional formula for torque is:
Which input (A, B) - output (Y) combination correctly represents the given logic circuit?
Two hollow conducting spheres of radii $R_1$ and $R_2$ ($R_1 \gg R_2$) are concentric and have equal charges. The potential would be:
The angle between the electric lines of force and the equipotential surface is:
Unit of stress is:
The velocity $v$ (in $\text{cm/sec}$) of a particle is given in terms of time $t$ (in $\text{sec}$) by the relation $v = at + \frac{b}{t+c}$; the dimensions of $a$, $b$ and $c$ are
A wire carrying current $I$ has the shape as shown in the adjoining figure. Linear parts of the wire are very long and parallel to X-axis while the semicircular portion of radius $R$ is lying in the Y-Z plane. The magnetic field at point $O$ is:
The effective capacitances of two capacitors are $3 \text{ \mu F}$ and $16 \text{ \mu F}$, when they are connected in series and parallel respectively. The capacitance of two capacitors are:
The pair having the same dimensions is:
Which does not have the same unit as others?
In an experiment four quantities $a$, $b$, $c$ and $d$ are measured with percentage error $1\%$, $2\%$, $3\%$ and $4\%$ respectively. Quantity $P$ is calculated as follows $P = \frac{a^3 b^2}{cd}$. The percentage error in $P$ is
Six charges +q, -q, +q, -q, +q and -q are fixed at the corners of a hexagon of side d as shown in the figure. The work done in bringing a charge q₀ to the centre of the hexagon from infinity is: (ε₀ - permittivity of free space)
Dimensions of $CR$ are those of:
The equation of a wave is given by $Y = A \sin \omega (\frac{x}{v} - k)$ where $\omega$ is the angular velocity, $x$ is length and $v$ is the linear velocity. The dimension of $k$ is:
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): The potential (V) at any axial point, at 2 m distance (r) from the centre of the dipole of dipole moment vector P of magnitude, $4\times10^{-6}$ C m, is $\pm 9\times10^3$ V. (Take $1/4\pi\varepsilon_0 = 9\times10^9$ SI units) Reason (R): $V = \pm \frac{2P}{4\pi\varepsilon_0 r^2}$, where r is the distance of any axial point situated at 2 m from the centre of the dipole. In the light of the above statements, choose the correct answer from the options given below:
In the following circuit, the equivalent capacitance between terminal A and terminal B is:
Dimensions of magnetic field intensity is:
Pick the wrong answer in the context with rainbow.