PHYSICS IMPORTANT QUESTIONS

1st year CSAQS
1. What is Physics?
2. What are the fundamental forces in nature?
3. Distinguish between accuracy and precision.
4. What are the different types of errors that can occur in a measurement?
5. How systematic errors be minimised or eliminated?
6. Distinguish between fundamental units and derived units.
7. Why do we have different units for the same physical quantity?
8. Express unified atomic mass unit in kg.
9. The vertical component of a vector is equal to its horizontal component. What is the angle made by the vector with X-axis?
10. Two forces of magnitudes 3 units and 5 units act at 600 with each other. What is the magnitude of their resultant?
11. A = i + j . What is the angle between the vector and x-axis?
12. When two right angled vectors of magnitude 7 units and 24 units combine, what is the magnitude of their resultant?
13. If P = 2i + 4j + 14k and Q = 4i + 4j + 10k find the magnitude of P +Q.
14. What is the acceleration of projectile at the top of its trajectory?
15. If a bomb at rest explodes into two pieces, the pieces must travel in opposite directions.explain.
16. Can the coefficient of friction be greater than one?
17. A horse has to pull harder during the start of the motion than latter. Explain.
18. Why does a heavy rifle not recoil as strongly as a light rifle using the same cartridges?
19. Is it necessary that a mass should be present at the centre of mass of any system?
20. Why should a helicopter necessarily have two propellers?
21. We can not open or close the door by applying force at the hinges why?
22. Why are spokes provided in a bicycle wheel?
23. Why do we prefer a spanner of longer arm as compared to the spanner of shorter arm.
24. If the polar ice caps of the earth were to melt what would the effect of the length of the day be ?
25. Define viscosity. What are its units and dimension formula?
26. What is the working principle of carburetor?
27. Why are water drops and Bubbles in spherical shape?
28. What is angle of contact?
29. What is Magnus effect?
30. Give the expression for excess pressure in a liquid drop?
31. Give the expression for the excess pressure in an air bubble inside the liquid?
32. Give the expression for excess pressure of soap bubble in air?
33. What are water proofing agents and water wetting agents? What do they do?
34. Mention any two examples or applications that obey Bernoulli’s theorem and justify them?
35. Define mean free path?
36. When does a real gas behave like an ideal gas?
37. State Dalton’s law of partial pressures?
38. Explain the concept of degrees of freedom for molecules of a gas?
39. What is the expression between pressure and kinetic energy of a gas molecule?
40. The absolute temperature of a gas is increased 3 times. What will be the increase in RMS velocity of the gas molecule?
41. State Boyle’s Law and Charles Law.

SAQ’s
1. How is average velocity different from instantaneous velocity?
2. A particle moves in a straight line with uniform acceleration. Its velocity at time t = 0is v1 and at time t = t is v2. The average velocity of the particle in this time interval is(v1 + v2)/2. Is this correct? Substantiate your answer.
3. Define unit vector,null vector and position vector.
4. If |a+b| = |a-b| prove that the angle between a and b is 900.
5. State parallelogram law of vectors. Derive an expression for the magnitude and direction of the resultant vector.
6. Show that the trajectory of an object thrown at certain angle with the horizontal is a parabola.
7. Explain advantages and disadvantages of friction.
8. Mention the methods used to decrease friction
9. State the laws of rolling friction.
10. Distinguish between centre of mass and centre of gravity?
11. Define vector product. Explain the properties of a vector product with two examples.
12. Define angular velocity. Derive v=rω
13. State and prove the principle of conservation of angular momentum. Explain the principle of conservation of angular momentum with examples.
14. Define angular acceleration and torque. Establish the relation between angular acceleration and torque.
15. What is orbital velocity? Obtain an expression for it.
16. What is escape velocity? Obtain an expression for it.
17. What is a geostationary satellite? State its uses.
18. Define Hooke’s law of elasticity, proportionality, permanent set and breaking stress.
19. Describe the behaviour of a wire under gradually increasing load.
20. Explain Celsius and Fahrenheit scales of temperature. Obtain the relation between Celsius and Fahrenheit scales of temperature?
21. Pendulum clocks generally go fast in winter and slow in summer why?
22. In what way is the anomalous behaviour of water advantageous to aquatic animals?
23. State and explain first law of thermodynamics?
24. Define two principle specific heats of gas? Which is greater and why?

LAQ’s
1. State and prove law of conservation of energy in case of a freely falling body.
A machine gun fires 360 bullets per minute and each bullet travels with a velocity of600 m/s. If the mass of each bullet is 5gm, find the power of the machine gun?
2. Develop the notions of work and kinetic energy and show that it leads to work-energy theorem.
A pump is required to lift 600 kg of water per minute from a well 25m deep and to eject it with a speed of 50m/s. Calculate the power required to perform the above task?
3. What are collisions? Explain the possible types of collisions. Develop the theory of one dimensional elastic collision.
4. Define simple harmonic motion. Show that the motion of (point) projection of a particle performing uniform circular motion, on any diameter, is simple harmonic
5. Show that the motion of a simple pendulum is simple harmonic and hence derive an equation for its time period. What is seconds pendulum?
6. State and explain Newton’s law of cooling? State the conditions under which newton’s law of cooling is applicable A body cools down from 60°C to 50°C in 5 minutes and to 40°C in another 8 minutes find the temperature of the surroundings?

2nd year VSAQ’s
1. Define focal length and radius of curvature of a concave lens.
2. What is optical density and how is it different from mass density?
3. Define power of a convex lens. What is its unit?
4. What is dispersion? Which colour gets relatively more dispersed?
5. What is myopia? How can it be corrected?
6. What is hypermetropia? How can it be corrected?
7. A small angled prism of 40 deviates a ray through 2.480. Find the refractive index of the prism.
8. What is the importance of Oersted’s experiment?
9. State Ampere’s law and Biot-Savart law.
10. Write the expression for the magnetic induction at any point on the axis of circular current carrying coil. Hence obtain an expression for the magnetic induction at the centre of the circular coil?
11. A circular coil of radius ‘r’ having ‘N’ turns carries a current i. What is its magnetic moment?
12. What is the force on a conductor of length ‘l’ carries a current ‘i’ placed in a magnetic field of induction B? When does it becomes maximum?
13. What is force on a charged particle of charge “q” moving with a velocity “v” in uniform ma gnetic field of induction B? When does it become maximum?
14. Distinguish between ammeter and voltmeter.
15. What is the principle of a moving coil galvanometer?
16. What is the smallest value of current that can be measured with a moving coil galvanometer?
17. How do you convert a moving coil galvanometer in to an ammeter?
18. A current carrying circular loop lies on a smooth horizontal plane. Can a uniform magnetic field be set up in such a manner that the loop turns about the vertical axis?
19. What happens to compass needles at the earth poles?
20. What do you understand by the magnetization of sample?
21. What are the units of magnetic moment, magnetic induction or magnetic field?
22. Magnetic lines from continuous closed loop why?
23. Define magnetic declination?
24. Define magnetic inclination (or) angle of dip?
25. A transformer converts 200V ac into 2000V ac. Calculate the number of turns in the secondary if the primary has 10 turns.
26. What type of a transformer is used in a 6V bed lamp?
27. What is the phenomenon involved in the working of a transformer?
28. What is transformer ratio?
29. Write the expression for the reactance of 1) an inductor and 2) a capacitor?
30. What is the phase difference between AC emf and current in the pure resistor, pure inductor and pure capacitor circuits?
31. When does a LCR series circuit have minimum Impedance?
32. If the wavelength of electro mag netic radiation is doubled,What happens to the energy of photon?
33. What is the principle of production of electromagnetic waves?
34. What is the ratio of speed of infrared rays and ultraviolet rays in vacuum?