CBSE
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. Then the two wires will have
the same stress and strain
the same stress but different strain
the same strain but different stress
different stress and strain
When a force F is applied on a wire oflength L and radius r, extension produce is l. If same force F is applied on the same material wire of length 2 L and radius 2r, then extension will be
l
2l
l/2
4l
A wire suspended vertically from one of its ends is stretched by attaching a weight 100 N to the lower end. The wire stretches by 1mm. The elastic energy stored in the wire is
0.02 J
0.05 J
0.1 J
0.2 J
A steel wire of length 15 m has density = 7.7 × 103 kg/m3 and Young's modulus = 2.2 × 1011 N/m2. It is subjected to a tension which produces an elastic strain of 1%. Its fundamental frequency of vibration must be
256 Hz
178 Hz
170 Hz
200 Hz
Which of the following has maximum property of elasticity?
Rubber
Lead
Wood
Steel
A circular metal plate of radius 5 cm rests on a layer of centre oil 2mm thick whose coefficient of viscosity is 15.5 dyne cm-2 s. The value of shearing stress when a horizontal force move the plate with a speed of 5 cm/s will be
387.5 dyne cm-2
328 dyne cm-2
250 dyne cm-2
428 dyne cm-2
Two wires of same material and length are stretched by the same force. Their masses are in the ratio 4 : 3. The ratio of their elongation will be
16 : 9
9 : 16
4 : 3
3 : 4
A solid sphere of radius r made of a material of bulk modulus K is surrounded by a liquid in cyliridrical container. The massless piston of area A floats on the surface of the liquid. If a mass m is placed on a piston to compress the liquid, then the fractional change in the radius of the sphere will be
Copper has face centred cubic (fcc) lattice with interatomic spacing equals to 2.54 . The value of lattice constant for this lattice is
3.59
2.54
1.27
5.08
Energy stored in the unit volume of a wire due to its elasticity is
stress/strain
force/strain