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Which one of the following statements is false?
If the lattice parameter for a crystalline structure is $3.6\text{ \AA}$, then the atomic radius in fcc crystal is:
For which one of the following, Bohr model is not valid ?
If in a p-n junction, a square input signal of $10 \text{ V}$ is applied as shown, then the output across $R_L$ will be:
Consider the following Statements A and B and identify the correct answer: Statement A: For a solar-cell, the I-V characteristics lies in the IV quadrant of the given graph. Statement B: In a reverse-biased pn junction diode, the current measured in ($\mu\text{A}$), is due to majority charge carriers.
Which one of the following represents the forward bias diode?
For transistor action: (a) the base, emitter and collector regions should have similar size and doping concentrations. (b) the base region must be very thin and lightly doped. (c) the emitter-base junction is forward biased and the base-collector junction is reverse biased. (d) both the emitter-base junction as well as the base-collector junction are forward biased. Which of the following pairs of statements is correct?
The Bohr model for the spectra of a H-atom: (a) will not apply to hydrogen in the molecular form. (b) will not be applicable as it is for a He-atom. (c) is valid only at room temperature. (d) predicts continuous as well as discrete spectral lines. Choose the correct option:
In a double slit experiment, when light of wavelength 400 nm was used, the angular width of the first minima formed on a screen placed 1 m away, was found to be 0.2°. What will be the angular width of the first minima, if the entire experimental apparatus is immersed in water? ($\mu_{water} = 4/3$)
Body A of mass 4m moving with speed u collides with another body B of mass 2m, at rest. The collision is head on and elastic in nature. After the collision the fraction of energy lost by the colliding body A is :
An AC voltage is applied to a resistance R and an inductor L in series. If R and the inductive reactance are both equal to 3 Ω, then the phase difference between the applied voltage and the current in the circuit will be:
In an alternating current circuit consisting of elements in series, the current increases on increasing the frequency of the supply. Which of the following elements are likely to constitute the circuit? (a) Only resistor (b) Resistor and an inductor (c) Resistor and a capacitor (d) Only a capacitor
The solids which have the negative temperature coefficient of resistance are:
Two bodies of mass $1 \text{ kg}$ and $3 \text{ kg}$ have position vectors $\hat{i}+2\hat{j}+\hat{k}$ and $-3\hat{i}-2\hat{j}+\hat{k}$, respectively. The centre of mass of this system has a position vector:
A small-signal voltage $V(t) = V_0 \sin(\omega t)$ is applied across an ideal capacitor C:
The given graph represents the V-I characteristic for a semiconductor device. Which of the following statements is correct?
A body is rolling without slipping on a horizontal surface and its rotational kinetic energy is equal to the translational kinetic energy. The body is:
The moment of inertia of a uniform circular disc of radius $R$ and mass $M$ about an axis touching the disc at its edge and normal to the disc is:
In the following circuit, the output Y for all possible inputs A and B is expressed by the truth table:
If the radius of the earth is suddenly contracted to half of its present value, then the duration of the day will be of: