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Obtain balanced condition of Wheatstone bridge circuit using Kirchhoff’s laws.
The figure below shows a series LCR circuit.
If the frequency of an ac source is 500/π Hz, then:
i) Calculate the phase angle between current and voltage. [2]
ii) Which one leads in phase, current or voltage? Justify. [1]
What is meant by impedance of an ac circuit?
Two parallel wire P and Q carrying currents I₁ and I₂ are placed in air at a distance r apart as shown in figure.
i) Obtain an expression for the magnitude of force per unit length between them. [2]
ii) What is the nature of force in this case? [1]
iii) What will be the force per unit length between two wires if distance between wire is halved, keeping all other quantities constant? [1]
The torque due to the gravitational force on a body about its centre of mass is:
finite
infinite
zero
not measurable
A gas undergoes a cyclic process ABCDA as shown in figure. The part ABC of process is semicircular. The work done by the gas is:
400π J
1200π J
2456 J
200π J
If refractive index of a glass is 1.5, what will be its polarizing angle?
65.3°
56.3°
45°
42.3°
For a thermocouple, the inversion temperature is 600°C and the neutral temperature is 320°C. Find the temperature of the cold junction
40°C
20°C
80°C
60°C
State the first law of thermodynamics and use it to explain why cooling effect is observed on adiabatic expansion?
In the given figure, a Carnot engine drives a Carnot refrigerator. Determine Q₂, Q₃ and Q₄.
On the basis of Young's double slit experiment, show that dark and bright fringes are equally spaced in interference.
What do you mean by current sensitivity and voltage sensitivity?
Obtain decay equation, N = N₀e⁻ˡᵗ, where symbols have their usual meanings.
The half life of radon is 3.8 days. Calculate how much radon will be left out of 1024 milligram after 38 days
A potentiometer circuit is shown in the figure.
If the total length of potentiometer wire is 4 m and has resistance 10 Ω and the balance point is obtained at a length of 240 cm, calculate the value of unknown emf E.
Use Ampere's circuital law to find the magnetic field due to a straight current carrying conductor.
Define threshold wavelength.
A metal has a work function of 2 eV. Calculate the maximum speed of the emitted photoelectrons when it is illuminated by radiation of wavelength 150 nm. What is the least frequency of the radiation for which electrons are emitted?
(Given: Planck's constant h = 6.62 × 10⁻³⁴ Js, m = 9.1 × 10⁻³¹ kg, e = 1.6 × 10⁻¹⁹ C)
State Heisenberg's Uncertainty principle.
Why does water form a concave meniscus but mercury forms convex meniscus inside a capillary tube of glass?