## 18 Questions

What is the null point obtained at when the unknown resistance X in the left gap is 40 Ω?

30 cm

When the resistance in each gap is increased by 15Ω, what is the new unknown resistance X in the left gap?

75 Ω

What is the inductance of the inductor connected to the A.C. source?

200 mH

If the peak e.m.f. is 210 V, what is the peak current in the circuit?

8 A

What type of gas process occurs when one mole of an ideal gas is allowed to expand till its volume is doubled at constant pressure?

Isobaric process

What is the key difference between streamline flow and turbulent flow?

Reynolds number

Which formula represents inductive reactance?

$X_L = \frac{L}{R}$

What is the concept of positive work done in a p-V diagram?

Expansion of the gas at constant pressure

What is the law of length for a vibrating string?

The length of the string is directly proportional to wavelength

What does the ratio of total current to full scale deflection current represent in a moving coil galvanometer?

Sensitivity coefficient

What does the de-Broglie wavelength associated with a particle depend on?

Momentum and velocity

What property determines the excess pressure inside a water drop?

Surface tension of water

In a resonance tube experiment, what is the formula for end correction?

$rac{1}{2}r$

Which dielectric is non-polar among the following?

CO2

What is the definition of potential gradient?

The rate of change of voltage with distance

For linear S.H.M., if the maximum speed of a particle is 0.08 m/s and the maximum acceleration is 0.32 m/s², what is the period of oscillation?

0.5 s

What are the conditions for current and impedance in a parallel resonance circuit?

Current is maximum, impedance is minimum

If the radius of the third Bohr orbit is 0.477 nm, what is the radius of the second Bohr orbit?

0.2385 nm

## Study Notes

### Meter Bridge

- Unknown resistance X in the left gap and 30 Ω in the right gap of a meter-bridge, null point is obtained at 40 cm from the left end of the wire.
- When resistance in each gap is increased by 15Ω, calculate the unknown resistance and shift in the position of the null point.

### Inductor and A.C. Source

- Inductor of inductance 200 mH is connected to an A.C.source of peak e.m.f. 210 V and frequency 50 Hz.
- Calculate the peak current and instantaneous voltage of the source when the current is at its peak value.

### Theorem of Parallel Axes

- State and prove theorem of parallel axes.

### Thermodynamic Processes

- Define:
- Isothermal process
- Adiabatic process

- One mole of an ideal gas is enclosed in an ideal cylinder at 1.0 mPa and 27°C. The gas is allowed to expand till its volume is doubled.
- Calculate the work done if the expansion is isobaric.

### Fluid Dynamics

- Distinguish between streamline flow and turbulent flow.
- Calculate the terminal velocity with which an air bubble of diameter 0.4 mm rises through a liquid of viscosity 0.1 Ns/m2 and density 900 kg/m3. Density of air is 1.29 kg/m3.

### Fraunhofer and Fresnel Diffraction

- Define:
- Fraunhofer diffraction
- Fresnel diffraction

- A plane wavefront of light of wavelength 5500Å is incident onto a slit perpendicular to the direction of light rays.
- Calculate the distance between the slits if the total separation of 10 bright fringes on a screen 2 m away is 2 cm.

### Transformers and Eddy Currents

- Define:
- Transformer

- Derive an expression for electric field intensity due to an infinitely long straight charged wire.
- Define eddy currents and write two applications.

### Inductive and Capacitive Reactance

- Define and state formulae for:
- Inductive reactance
- Capacitive reactance

### Work and Energy

- Draw a p –V diagram and explain the concept of positive work done and negative work done.

### Vibrating String

- State the law of length and the law of linear density for a vibrating string.

### Moving Coil Galvanometer

- For a moving coil galvanometer, show that S = G , n 1 where S is shunt resistance, G is galvanometer resistance, and n is the ratio of total current to the full scale deflection current.

### De-Broglie Wavelength

- The de-Broglie wavelengths associated with an electron and a proton are the same.
- Calculate the ratio of their kinetic energies.

### Radioactive Decay

- Derive an expression for 'Half Life Time' of a radioactive material using the ‘Law of Radioactive Decay’.

### Motorcyclist Stunt

- A motorcyclist performs a stunt along the cylindrical wall of a ‘Well of Death’ of inner radius 4 m.
- Coefficient of static friction between the tyres and the wall is 0.4.
- Calculate the maximum period of revolution.

### Water Drop Diameter

- Calculate the diameter of a water drop if the excess pressure inside the drop is 80 N/m2.
- Surface Tension of water = 7.2 × 10–2 N/m

Solve for the unknown resistance in a meter-bridge setup and the shift in null point position when resistances are increased. Also, calculate the peak current and instantaneous voltage in an AC circuit with an inductor of known inductance and source values.

## Make Your Own Quizzes and Flashcards

Convert your notes into interactive study material.

Get started for free