Mechanical Properties of solids

The cause of elasticity of a substance is

• deformation

• large internal restoring force

• low internal restoring force

• less distance between the molecules

The graph of stress against strain is always

• straight line

• parabola

• Straight line in elastic region

• parabola in elastic region

Young's modulus is property of

• solids

• solids and liquids

• solids or liquids

• gases

There are two identical wires with Young's moduli Y1 and Y2 respectively such that Y1> Y2. If they are hung from a rigid support and same weight is applied to them at their free ends then

• elongation in the wires will be same

• elongation in the first wire will be more

• First wire will constrict more

• Elongation in the second wire will be more

1 N/m² = ____ dyne /cm²

• 1

• 1000

• 100

• 10

The bulk modulus of a material of a wire 1m long is B. So the bulk modulus of a 2m long wire of same material will be

• 2B

• B

• 2/B

• B/2

A balloon 's volume decreases by 1% when its pressure is increased by 80%. So its Bulk modulus is

• 80 unit

• 1/80 unit

• 1 unit

• 800 unit

If a force of 4 N is applied across a face of a cube whose sides are 2mm each then stress produced is

• 16N/m²

• 10⁶N/m²

• 1

• 4

Compressibility is reciprocal of

• Young's modulus

• Modulus of elasticity

• Shear modulus

• Bulk modulus

If a wire breaks just after plastic flow begins then material is

• strong

• hard

• brittle

• ductile