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The increase in the width of the depletion region in a p-n junction diode is due to:
A 220V input is supplied to a transformer. The output circuit draws a current of 2.0A at 440V. If the efficiency of the transformer is 80%, the current drawn by the primary windings of the transformer is
Energy E of a hydrogen atom with principal quantum number n is given by E = -13.6/n² eV. The energy of a photon ejected when the electron jumps from n = 3 state to n = 2 state of hydrogen, is approximately:
In a series LCR circuit, the inductance $L$ is 10 mH, capacitance $C$ is 1 $\mu$F and resistance $R$ is 100 $\Omega$. The frequency at which resonance occurs is:
The maximum power is dissipated for an AC in a/an:
Three blocks A, B, and C of masses $4 \text{ kg}$, $2 \text{ kg}$, and $1 \text{ kg}$ respectively, are in contact on a frictionless surface, as shown. If a force of $14 \text{ N}$ is applied to the $4 \text{ kg}$ block, then the contact force between A and B is:
As the frequency of an AC circuit increases, the current first increases and then decreases. Which of the following combinations of circuit elements is most likely to comprise the circuit? (a) Inductor and capacitor (b) Resistor and inductor (c) Resistor and capacitor (d) Resistor, inductor, and capacitor
Three blocks A, B and C of masses $4 \text{ kg}$, $2 \text{ kg}$ and $1 \text{ kg}$ respectively, are in contact on a frictionless surface, as shown. If a force of $14 \text{ N}$ is applied on the $4 \text{ kg}$ block, then the contact force between A and B is:
The potential differences across the resistance, capacitance and inductance are 80 V, 40 V and 100 V respectively in an LCR circuit. What is the power factor of this circuit?
The core of a transformer is laminated so that:
Four charges each equal to $Q$ are placed at the four corners of a square and a charge $q$ is placed at the centre of the square. If the system is in equilibrium, then the value of $q$ is:
Two carts of masses 200 kg and 300 kg on horizontal rails are pushed apart. Suppose the coefficient of friction between the carts and the rails are the same. If the 200 kg cart travels a distance of 36 m and stops, then the distance travelled by the cart weighing 300 kg is:
An inductor of inductance L, a capacitor of capacitance C and a resistor of resistance R are connected in series to an AC source of potential difference V volts. The potential difference across L, C and R is 40 V, 10 V and 40 V, respectively. The amplitude of the current flowing through the LCR series circuit is $10\sqrt{2}$ A. The impedance of the circuit will be:
A block of mass $m$ is in contact with the cart C as shown in the figure. The coefficient of static friction between the block and the cart is $\mu$. The acceleration $\alpha$ of the cart that will prevent the block from falling satisfies:
A balloon with mass $m$ is descending down with an acceleration $a$ (where $a < g$). How much mass should be removed from it so that it starts moving up with an acceleration $a$?
A body, under the action of a force $\vec{F} = 6\hat{i} - 8\hat{j} + 10\hat{k}$, acquires an acceleration of $1 \text{ ms}^{-2}$. The mass of this body must be:
A series LCR circuit containing 5.0 H inductor, 80 μF capacitor and 40 Ω resistor is connected to 230 V variable frequency AC source. The angular frequencies of the source at which power transferred to the circuit is half the power at the resonant angular frequency are likely to be:
A $100 \, \Omega$ resistance and a capacitor of $100 \, \Omega$ reactance are connected in series across a $220$ V source. When the capacitor is $50\%$ charged, the peak value of the displacement current is:
Match List-I with List-II. List-I (Spectral Lines of Hydrogen for transitions from) A. n₂=3 to n₁=2 B. n₂=4 to n₁=2 C. n₂=5 to n₁=2 D. n₂=6 to n₁=2 List-II (Wavelength (nm)) I. 410.2 II. 434.1 III. 656.3 IV. 486.1 Choose the correct answer from the options given below:
A car of mass $1000 \text{ kg}$ negotiates a banked curve of radius $90 \text{ m}$ on a frictionless road. If the banking angle is $45^\circ$, the speed of the car is: