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Page 1: Experiment 1 - Oscillations and Hooke's Law

Multiple Choice Questions:
1. (1) (a) Free Oscillations
2. (2) (d) Fourth power of the radius of the wire of the spring
- Solution: T^2 ∝ 0.5s; T = 1s; vmax = ωA = 2π/T * A => 2π/0.1 = 0.2π m/s
1. (3) (c) The number of turns
2. (4) (b) 0.2π m/s
3. (5) (a) 1 or 4 times
4. (6) (c) 128 N/m
Questions:
1. Hooke's Law:
  - States that for elastic strain up to the proportional limit, stress is directly proportional to strain (Stress ∝ Strain).
  - Restoring force affects the deformation.
2. Force Constant (k):
  - Defined as the deforming force per unit deformation: k = η r^4 / (4NR^3)
  - Where r = radius of wire, R = radius of helix, N = number of turns, η = modulus of rigidity.
3. Linear Simple Harmonic Motion (SHM):
  - Periodic motion where acceleration is directed towards the mean position and is proportional to the displacement from it.

Page 2: Properties of Oscillations

Damped Oscillations:
- Oscillations with gradually decreasing amplitude due to dissipative forces (e.g., air resistance).
Forced Oscillations:
- Occur in response to an external periodic force.
Acceleration in SHM:
- Proportional to displacement from the mean position (variable acceleration).
Period of a Vertical Spring:
- Proportional to the square root of total mass (m = suspended mass + effective mass);
- Independent of amplitude if small;
- Inversely proportional to the square root of the force constant.
Calculating g:
- From T^2 = 2π^2 x / g; hence g can be derived from mean T^2.

Page 3: Experiment 2 - Surface Tension and Cohesion

Multiple Choice Questions:
1. (1) (a) Cohesive Force
2. (2) (b) Adhesive Force
3. (3) (a) Acute
4. (4) (b) Liquid falls in tube.
5. (5) (a) 2.6 cm
- Solution: hr = constant => h2 = (h1 * r1) / r2 = (5.2 * 0.2) / 0.4 = 2.6 cm
Questions:
1. Defining Surface Tension:
  - Defined as the tangential force per unit length acting at right angles on either side of an imaginary line on the liquid's surface.
2. Factors Affecting Surface Tension:
  - Depends on cohesive forces, temperature, and impurities: increases with dissolved impurities, decreases with insoluble impurities.
3. Capillarity:
  - Depends on surface tension, density of the liquid, contact angle, capillary bore radius, and gravity.
4. Effect of Impurities on Surface Tension:
  - Cleaning capillaries ensures precise measurements; Oily fingers can affect outcomes.

Page 4: Practical Considerations in Surface Tension

Backlash Error:
- Present in screws of measuring instruments; should rotate in one direction during readings.
Effects of Air Bubbles:
- Can affect capillary rise and surface tension calculations.
Examples of Capillary Action:
1. Blotting paper absorbs liquids.
2. Oil rises in wicks.
3. Groundwater rises through soil pores.
4. Water causes rocks to crumble through expansion/contraction.

Page 5: Experiment 3 - Heat Transfer and Cooling

Multiple Choice Questions:
1. (1) (d) Newton’s Law of Cooling
2. (2) (c) Processes (I) and (II)
3. (3) (b) Rate S
4. (4) (c) 7.8°C/min
- Solution: Using Newton’s law: dT/dt ∝ (body temp - ambient temp).
Questions:
1. Newton’s Law of Cooling:
  - Rate of heat loss is directly proportional to the excess temperature, within small excess limits.
2. Cooling Rate Factors:
  - Mass, specific heat, emissivity, surface area.
3. Cooling Curve:
  - Shows exponential decrease similar to radioactive decay and capacitor discharge.
4. Energy Loss Equation:
  - dQ/dt = mS * dT/dt = K(T - T0).

Page 6: Advanced Calculations in Cooling

Example Cooling Calculation:
1. Using cooling rates and the surrounding temperature.
Calculating Internal Resistance:
1. Relation between temperature and time taken to cool down.

Page 7: Experiment 4 - Sound and Wave Properties

Multiple Choice Questions:
1. (1) (c) Amplitude, Wavelength, and Speed
2. (2) (b) Fundamental
3. (3) (a) Radius of the Wire
4. (4) (b) 2L
5. (5) (b) 20 m/s
- Solution:
  - Distance between nodes => λ/2;
  - λ = 0.2 m, v = nλ subbing values yields 20 m/s.
Questions:
1. Law of Length:
  - Fundamental frequency inversely prop. to vibrating length (Tension and mass are constant).
2. Forced Vibrations:
  - Maximum amplitude at natural frequency, leading to resonance.
3. Nodes and Antinodes:
  - Particles at nodes are still; antinodes maximize vibration.
4. Harmonics Definition:
  - Fundamental is first harmonic, overtones are integral multiples thereafter.

Page 8: Resonance and Stationary Waves

Characteristics of Vibrating Wire:
- Nodes at fixed ends, antinode at center. Flutters indicate harmonics.
Beats in Sound:
- Variations in loudness occurring when different frequencies sound together.
Fundamental Frequency Relation:
- Determined by density, length, and tension equations.

Page 9: Experiment 5 - Tuning Forks and Wave Properties

Multiple Choice Questions:
1. (1) (b) The end resistances
2. (2) (a) Increase
3. (3) (b) Decrease to Zero
4. (4) (a) Basic setup for high sensitivity.
5. (5) (b) 4 mA
Questions:
1. Sensitivity and Resistance:
  - Correlation determined through temperature differentials.
2. Effects of Current & Resistance:
  - Addressing changes during operations.

Page 10: Experiment 6 - Waves and Resonance

Multiple Choice Questions:
1. (1) (b) l = potential gradient
2. (2) (c) Voltmeter
3. (3) (a) 30 mV
Questions:
1. Progressive vs Stationary Waves:
  - Waves transport energy vs stationary doesn’t.
2. Tuning Fork Mechanics:
  - Establishing resonance through tuned air column.

Page 11: Experiment 7 - Thoughts on Magnetism

Multiple Choice Questions:
1. (1) (b) IAB
2. (2) (b) Torque constant of spring
3. (3) (d) both (b) and (c)
Questions:
1. Principle of Torque in Coil:
  - Operating within magnetic fields to maximize performance.
2. Current Sensitivity Defined:
  - Ratio of deflection to changes in current.

Page 12: Experiment 8 - Electrical Measurements and Galvanometers

Multiple Choice Questions:
1. (1) (d) R4
Questions:
1. Potentiometer Setup:
  - Measures potential differences directly; stable source.
2. Measurement Principles:
  - Significance of long wire setup.

Page 13: Experiment 9 - Resistance and Errors

Multiple Choice Questions:
1. (1) (d) all of the above
Questions:
1. Understanding Internal Resistance:
  - Factors affecting responses based on interactions.

Page 14: Experiment 10 - Voltage and Electrical Concepts

Multiple Choice Questions:
1. (1) (b) Voltage Gradient
Questions:
1. Potentiometer vs Voltmeter:
  - Advantages of measuring open circuit directly.

Page 15: Experiment 11 - Properties of Circuits

Multiple Choice Questions:
1. (1) (b) Increase
Questions:
1. Current Definitions:
  - Flows affected by material properties.

Page 16: Experiment 12 - Magnetic Moments and Torque

Multiple Choice Questions:
1. (1) (c) Increased toggling.
Questions:
1. Vibration Magnetometer Principle:
  - Dependence on positioning within magnetic fields.

Page 17: Experiment 13 - Rectifiers and Breakdown

Multiple Choice Questions:
1. (1) (b) Breakdown occurrences.
Questions:
1. Zener Diode Functioning:
  - Special properties under varying conditions.

Page 18: Experiment 14 - Logic Gates and Functions

Multiple Choice Questions:
1. (1) (c) Functionality under distinct inputs.
Questions:
1. Basic Logic Gate Operations:
  - Functions of AND, OR, NOT explained.

Page 19: Experiment 15 - Transistor Characteristics

Multiple Choice Questions:
1. (1) (d) Application details explained.
Questions:
1. Transistor Structure and Functionality:
  - Detailed explanation on construction and operational biasing.