Optics Answers

A block of glass with refractive index,w.5 is surrounded by air. A rat of light enters the block at its left-hand face with incident angle X and reemerges into the air from the right-hand face directed parallel to the block's base. Find X

A string 50.0 cm long has a mass per unit length equal to 20.0x10^-5 kg/m. To what tension should this string be stretched if it's fundamental frequency is to be 20.0 Hz.

Interference fringes are produced by monochromatic light falling normally on a wedge shaped film of cellophane of refractive index 1.4. If angle of wedge is 20 seconds of an arc and the distance between successive fringes is 0.25 cm, calculate the wavelength of light.

a) An airplane trip involves three legs, with two stopovers. The first leg is due East for 620 km; the second leg is Southeast (45°) for 440 km; and the third leg is at 53° South of West, for 550 km.

i. Draw a figure showing the journey.

ii. What is the plane's total displacement and direction? 

How far apart are an object and an image formed by a 75.0cm focal length converging lens if the image is 2.5x larger than the object and is real.

Suppose a concave neniscus lens is made firom glass with n = 1.50, with a focal length of 50.0cm and the radius of curvature of the concave surface is 30.0cm. 

i. What is the radius of curvature of the convex surface? Is this a diverging lens or a converging lens? (2 marks)

ii. If I were to use the same lens to magnify a small insect using the same focal length to form a Virtual image, that is, 45.0cm in front of the lens; where should the small insect be

placed? (2 marks)

Conclusion for Free falling