Wednesday, 1 October 2014

ELASTICITY MULTIPLE CHOICE QUESTIONS

1. When a certain weight is suspended from a long uniform wire, its length increases by one cm. If the same weight is suspended from another wire of the same material and length but having a diameter half of the first one then the increase in length will be . [CPMT 1984, 90]

2. The bulk modulus of an ideal gas at constant temperature . [MP PMT 2004]


3. The longitudinal strain is only possible in

4. The area of cross-section of a wire of length 1.1 metre is 1 mm2. It is loaded with 1 kg. If Young's modulus of copper is 1.1 * 1011 N/m2 , then the increase in length will be (If g = 10). [MP PET 1989]

5. If Young's modulus of iron is 2*1011 N/m2 and the interatomic spacing between two molecules is 3*10-10metre, the interatomic force constant is . [JIPMER 1978]

6. The isothermal elasticity of a gas is equal to . [CPMT 1981; MP P]


7. A steel wire is stretched with a definite load. If the Young's modulus of the wire is Y. For decreasing the value of Y

8. The force constant of a wire does not depend on

9. The elasticity of invar

10. The ratio of the lengths of two wires A and B of same material is 1 : 2 and the ratio of their diameter is 2 : 1. They are stretched by the same force, then the ratio of increase in length will be. [MP PET/PMT 1988]

11. Which statement is true for a metal. [DPMT 2001]

12. The Young's modulus of a wire of length L and radius r is Y N/m2. If the length and radius are reduced to L/2 and r/2, then its Young's modulus will be . [MP PET 1997; KC]

13. If the temperature increases, the modulus of elasticity


14. After effects of elasticity are maximum for


15. The ratio of lengths of two rods A and B of same material is 1 : 2 and the ratio of their radii is 2 : 1, then the ratio of modulus of rigidity of A and B will be
16. Hook's law defines . [MP PMT/PET 1988]

17. In a wire of length L, the increase in its length is l. If the length is reduced to half, the increase in its length will be


18. Modulus of rigidity of diamond is

19. The extension of a wire by the application of load is 3 mm. The extension in a wire of the same material and length but half the radius by the same load is . [CMEET Bihar 199]


20. Density of rubber is d. A thick rubber cord of length L and cross-section area A undergoes elongation under its own weight on suspending it. This elongation is proportional to
21. The compressibility of a material is

22. If Young's modulus for a material is zero, then the state of material should be

23. The quality of the material which opposes the change in shape, volume or length is called

24. A wire extends by 1 mm when a force is applied. Double the force is applied to another wire of same material and length but half the radius of cross-section. The elongation of the wire in mm will be. [EAMCET 1986]

25. If the length of a wire is reduced to half, then it can hold the ......... load

26. The ratio of the adiabatic to isothermal elasticities of a triatomic gas is. [MP PET 1991]

27. The possible value of Poisson's ratio is . [EAMCET (Med.) 1]


28. The dimensions of four wires of the same material are given below. In which wire the increase in length will be maximum when the same tension is applied . [IIT 1981;CPMT 1]

29. The increase in length is l of a wire of length L by the longitudinal stress. Then the stress is proportional to .[MP PET 1986]

30. Two wires of equal lengths are made of the same material. Wire A has a diameter that is twice as that of wire B. If identical weights are suspended from the ends of these wires, the increase in length is . [MP PMT 1990; MP]
31. A and B are two wires. The radius of A is twice that of B. They are stretched by the some load. Then the stress on B is . [MP PMT 1993]

32. Which one of the following quantities does not have the unit of force per unit area. [MP PMT 1992]


33. When compared with solids and liquids, the gases have


34. A copper wire and a steel wire of the same diameter and length are connected end to end and a force is applied, which stretches their combined length by 1 cm. The two wires will have. [MP PMT 1992]

35. Two identical wires of rubber and iron are stretched by the same weight, then the number of atoms in the iron wire will be . [DPMT 1999]



36. When a spiral spring is stretched by suspending a load on it, the strain produced is called

37. The material which practically does not show elastic after effect is. [JIPMER 1997; AM]

38. The spring balance does not read properly after its long use, because


39. Two wires of copper having the length in the ratio 4 : 1 and their radii ratio as 1 : 4 are stretched by the same force. The ratio of longitudinal strain in the two will be

40. In the three states of matter, the elastic coefficient can be


41. A rod of length l and area of cross-section A is heated from 0°C to 100°C. The rod is so placed that it is not allowed to increase in length, then the force developed is proportional to . [NCERT 1976]

42. A force F is needed to break a copper wire having radius R. The force needed to break a copper wire of radius 2R will be . [MP PET 1990]


43. Modulus of rigidity of a liquid. [RPET 2000]

44. If the density of the material increases, the value of Young's modulus


45. Increase in length of a wire is 1 mm when suspended by a weight. If the same weight is suspended on a wire of double its length and double its radius, the increase in length will be . [CPMT 1976]