Mechanical Prop...

The Young's modulus of a rubber string 8 cm long and density 1.5 $$kg/m^{3}$$ is $$5\times 10^{8} N/m^{2}$$, is suspended on the ceiling in a room. The increase in length due to its own weight will be:-

In a  young's double-slit experiment, the slits are separated by $$0.5 mm$$, and the screen is placed $$150 cm$$ away. A beam of light consisting of two wavelengths, $$650 nm$$, and $$520 nm$$, is used to obtain interference fringes on the screen. The least distance from the common central maxima to the point where the bright fringes due to both the wavelengths coincide is:  

An iron wore and copper wire having same length and cross-section are suspended from same roof Young's modulus of copper is $$\dfrac 13$$ that of iron. Then the ratio of the weights to be added at their ends so that their ends are at the same level is

If the work done in stretching a wire by $$1\ mm$$ is $$2\ J$$, then work necessary for stretching another wire of same material but with double radius of cross-section and half of the length by $$1\ mm$$ is 

An elongation of $$0.1^\circ$$ in a wire of cross sectional area $$10^{-6}m^{2}$$ causes a tension of 100n. The Young's modulus is-

A $$40\ cm$$ wire having a mass $$3.2\ gm$$ and area of cross-section $$1\ mm^{2}$$ is stretched between two supports $$40.05\ cm$$ apart. In its fundamental note, the wire vibrates with a frequency $$220\ Hz$$. The Young's molulus is :

A steel wire (original length = 2m, diameter = 1mm) and a copper wire ( original length =1m, diameter =2mm) are loaded as shown in  the figure . Find the ratio of extension of steel wire to that of copper wire. Given , Young's modulus of steel = $$2\times  10^{11} Nm^{-2}$$ and that of copper is $$  10^{11} Nm^{-2}$$.

A body of mass 1 Kg is fastended to one end of a steel wire of cross - sectional area 3$$\times 10^{-6}$$ m$$^{2}$$ and it rotated in horizontal circle of radius 20 cm with a constant speed of 2 m/s .The elongation in the wire is (Y = 2$$\times 10^{11}$$N / m$$^{2}$$)

The force required to punch a square hole 2 cm side in steel sheet 2 mm thick is:-
(shearing stress of steel sheet $$=3.5 \times10^8 N/m^2)$$

A man grows into a giant such that his linear dimensions increase by  a factor of $$9$$. Assuming that his density remains same, the stress in the leg will change by a factor of?