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A vessel has 6 g of hydrogen at pressure P and temperature 500 K. A small hole is made in it so that hydrogen leaks out. How much hydrogen leaks out if the final pressure is and temperature falls to 300 K? (a) 2 g (b) 3g (c) 4g (d) 1 g

PV=-RT 6 Initially, PV =-Rx 500

Finally, (if x g gas leaks out) P,/ = (6-x) RX 300 2 Dividing eqn. (i) by (ii), we get 6 x3

Interference fringes were produced in Young's double slit experiment using light of wavelength 5000 . When a film of material 2.5 x 10-3 cm thick was placed over one of the slits, the fringe pattern shifted by a distance equal to 20 fringe widths. The refractive index of the material of the film is

Fringe width where D is the distance between the screen and slit and d is the distance between two slits. When a film of thickness t and refractive index u is placed over one of the slit, the fringe pattern is shifted by distance S and is given by Given, S 20B

From equations (i), (ii) and (iii) we get, 20>< 5000 >< 10-8 cm 2.5 x103 cm 20 ( -1) or or

A compound microscope has an eye piece of focal length 10 cm and an objective of focal length 4 cm. Find the magnification, if arn object is kept at a distance of 5 cm from the objective, so that the final image is formed at the least distance of distinct vision 20 cm. (a) 12(b) 11 (c) 10 (d) 13

Here, uo5 cm, f 4 =10cm, D = 20 cm According to lens formula or tl uo Substituting the given values, we get v 4 5 4 5 20 v = 20 cm