CBSE
Two wires are made of the same material and have the same volume. The first wire has cross-sectional area A and the second wire has cross-sectional area 3A. If the length of the first wire is increased by Δl on applying a force F, how much force is needed to stretch the second wire by the same amount?
9F
6F
F
4F
Two bars A and B of circular cross-section and same volume made of same material are subjected under same tension. If the diameter of A is half that of B. The ratio of extension of A to B will be
16
2
4
The dimensional formula for Young's modulus is
A wire can be broken by applying load of 200 N. The force required to break another wire of the same length and same material, but double in diameter is
200 N
400 N
600 N
800 N
If Young's double slit experiment is performed i water instead of air, then
no fringes would be seen
fringe width would decrease
fringe width would increase
fringe width would remain unchanged
A fixed volume of iron is drawn into a wire of length l. The extension x produced in this wire by a constant force F is proportional to
l
A cube of side 40 mm has its upper face displaced by 0.1 mm by a tangential force of 8 kN. The shearing modulus of cube is
2 × 109 Nm-2
4 × 109 Nm-2
8 × 109 Nm-2
16 × 109 Nm-2
A ball falling in a lake depth 200 m shows a decrease of 0.1 % in its volume at the bottom then the bulk modulus of the material of the ball is
The maximum number of possible interference maxima for slit-separation equal to twice the wavelength in Young's double slit experiment is
infinite
five
three
zero
The fundamental frequency in an open organ pipe is equal to the third harmonic of a closed organ pipe. If the length of the closed organ pipe is 20 cm, the length of the open organ pipe is
13.2 cm
8 cm
16 cm
12.5 cm