ENGINEERING PHYSICS TUTORIAL PROBLEMS

1. 1.      Sodium light of wavelength 6000A⁰ is a doublet of 6500A⁰. What is the minimum number of lines in a grating should have to resolve the doublet in the third order spectrum
   2.      What is the highest order that can be seen if a grating with 6000 lines per cm is illuminated by a source of 650nm wavelength
   3.      Interference fringes are formed in thin air-wedge using sodium light when observed normally. 10 fringes are found in a distance 1µm. Calculate the angle of wedge.
   4.      A wave of wavelength .30m is travelling down in 300m long wire, whose total mass is 15kg. If the wire is under tension of 1000N. What is the velocity and frequency of the wave?
   5.      The equation of a transverse wave travelling coil spring y= 5sinπ(0.10x-2t) where x and y in cm and t in sec. Find amplitude, wavelength, initial phase at the origin, speed and frequency.
   6.      The equation of a wave travelling string y= 5cosπ(0.5x-200t) where x and y in cm and t in sec. Find amplitude, wavelength, time period, speed and frequency.          
   7.      What is the highest order that can be seen if a grating with 6000 lines per cm is illuminated by a source of 650nm wavelength
   8.      Calculate the angle of the air-wedge to form uniform fringes of thickness 0.01cm for a monochromatic light of wavelength 6000A⁰
   9.      In Newton’s rings experiment the diameter of the 4^th  and 12^th dark ring are 0.4cm and 0.7cm. Obtain the diameter of 20^th dark ring.
   10.  A parallel beam of monochromatic light is allowed to fall normally on a plane transmission grating having 6000lines/cm and the first order is maximum which is formed at 15⁰10’. Calculate the wavelength of light.
   11.  A soap film of refractive index 1.43 is illuminated by white light incident at an angle of 30⁰. The refracted light is examined by a spectroscope in which dark band corresponding to the λ = 6× 10^-7m is observed. Calculate the thickness of the film.
   12.  Newtons rings are formed in reflected light of λ = 6000A⁰ with a liquid between the lane and curved surfaces. If the diameter of the 6^th bright ring is 3.1 mm and the radius of curvature of the curved surfaces is 100 cm. Calculate the refractive index of the liquid.
   13.  A piece of wire 50 cm long is stretched by a load of 2.5kg and has a mass of 1.44gm. Find the frequency of second harmonic?
   14.  Determine the Amplitude, Period, Frequency, Speed and λ of the waves represented by  y=0.02 sin 2(3t-2x)
   15.  Light of λ= 589.3 nm is incident normally on a plane transmission grating having 6000 lines/cm. Calculate the angle at which the principal maxima of the first order is formed.
   16.  Newtons rings are formed in reflected light of λ = 6000A⁰ with a liquid between the lane and curved surfaces. If the diameter of the 6^th bright ring is 3.1 mm and the radius of curvature of the curved surfaces is 100 cm. Calculate the refractive index of the liquid.
   17.  Find the equation of a wave of amplitude 2cm, period 0.5cm and velocity 200cm/s moving along the x- axis.