Download applied science viva questions

APPLIED SCIENCE
VIVA QUESTIONS
1. What is the principle of vernier?
The principle of vernier is that “n”divisions of vernier scale are equal to “(n-1)” divisions of main
scale.
2. What is the meaning of least count?
The least measurement that can be measured using an instrument is called as the least count.
3. What is the least count of ordinary scale?
Least count of ordinary scale is 0.1cm.
4. What is the least count of wall clock?
Least count of wall clock is One second
5. Define pitch of the screw.
Pitch is defined as the ratio of distance uncovered on the pitch scale in mm to the number of full
rotations given to the screw head.
6. What is the relation between least count and accuracy?
As the least count decreases, accuracy increases.
7. What is the advantage of screw gauge over slide calipers?
Screw gauge gives more accuracy than slide calipers.
8. Define Resultant, Equilibrant and Equilibrium.
Resultant: It is a single force which produces same effect as produced by a system of forces.
Equilibrant: It is a single force which cancels the effect produced by a system of forces.
Equilibrium: A body is said to be in equilibrium when the net effect of all forces acting on it is
zero.
9. What is the relation between Resultant and Equilibrant?
Resultant and equilibrant are equal in magnitude and opposite in direction.
R=-E
10. State law of parallelogram of forces.
“If two forces acting at a point are represented by two sides of a parallelogram then resultant
force is given by the diagonal passing through that point”.
11. State the law of triangle of forces.
“If three forces acting at a point are in equilibrium, then they can be represented both in
magnitude and direction by three sides of a triangle taken in order.”
12. State lami’s theorem
“If three forces acting at a point are in equilibrium then each force is directly proportional to
sine of the angle between the other two forces”.
13. State the condition of equilibrium.
1). Sum of forces acting in one direction is equal to the sum of forces acting in the opposite
direction.
2). Sum of clockwise moments is equal to sum of anti-clockwise moment.
14. Define moment of force or torque.
Rotating effect of force is called moment of force or effect of force to rotate a body is called
moment.
15. What is force? What is its SI unit?
Force is a push or pull which sets in or stops the motion of an object.
SI unit of force is Newton.
16. Define frequency? What is its SI unit?
Frequency is defined as the number of cycles per second. Its SI unit is hertz.
17. In sonometer experiment a paper rider is kept on the wire. Why?
In sonometer experiment a paper rider is kept on the wire in order to sense the vibration of the
string or wire.
18. What is resonance?
The phenomena of a vibratory motion produced in one body due to the influence of another
body having the same frequency as the first is called resonance.
19. Soldiers are asked to break the steps when they approach a hanging bridge. Why?
Because when resonance occurs, the bridge may collapse.
20. Define linear density of wire? What are its units?
Linear density of wire is defined as its mass per unit length. its SI unit is g/cm or kg/m.
21. What is NTP.
NTP is normal temperature pressure.
22. What is the value of velocity of sound in air at NTP?
Value of velocity of sound in air at NTP is 332m/s
23. Define surface tension.
The surface of the liquid is always in a state of tension the force of tension that exists. Over the
surface of the liquid is called surface tension.
24. What are the factors which affect surface tension?
1) Surface tension of a liquid decreases with increase in temperature.
2) Surface tension can be altered by contaminating surface of liquid.
3) Surface tension of the liquid can be lowered by adding some practically soluble impurities
25. Define viscous force and viscosity?
The property of liquid by virtue of which it opposes relative motion between its different layers
in known as viscosity.
The tangential force acting on the liquid layer which tends to reduce its forward motion is called
viscous force.
26. What are the factors which affect viscosity of liquids?
Viscosity of liquids decreases as the temperature of the liquids increases.
27. What is lubrication?
Introduction of a thin layer of oil between the moving surfaces of machines to reduce the
friction between them is known as lubrication.
28. Define stress and strain. Mention the units of stress and strain?
Stress us defined as applied force per unit area to which force is applied.
Its SI unit is N/M2.
Strain is the amount of change in shape or size of the object.
Strain has no unit.
29. State Hooke’s law.
Within elastic limit stress is directly proportional to strain.
30. What is modulus of elasticity
Modulus of elasticity is defined as the ratio of stress to the strain produced with in elastic limit.
31. What is young modulus of elasticity? What is its SI unit?
𝑡𝑒𝑛𝑠𝑖𝑙𝑒 𝑠𝑡𝑟𝑒𝑠𝑠
Young’s modulus = 𝑡𝑒𝑛𝑠𝑖𝑙𝑒 𝑠𝑡𝑟𝑎𝑖𝑛.
Its SI unit is N/m2.
32. What is capillarity?
Whenever a capillary tube is dipped in a liquid the liquid rises or falls in the tube. This
phenomenon is called capillarity.
33. Define Simple harmonic motion.
To and fro motion, which repeats again and again at equal intervals of time is called simple
harmonic motion.
34. What kind of waves are radio waves
Radio waves are non-mechanical and longitudinal waves.
35. State Boyle’s law.
At constant temperature volume of given mass of gas is inversely proportional to pressure of
gas.
36. State charle’s law.
At constant pressure volume of gas is directly proportional to the absolute temperature.
37. State Gay-lussac’s law.
When volume of gas is kept constant pressure varies directly with absolute temperature.