Write expression for the magnification produced by a lens system.

Write expression for mass defect.

Write expression for the angular dispersion produced by a prism.

Write an expression for the magnetic field produced by an infinitely long straight wire carrying a current I, at a short perpendicular distance a from itself.

A concave lens has focal length of 15 cm. At what distance should the object from the lens be placed so that it forms an image at 10 cm from the lens? Also find the magnification produced by the lens.

Two lenses convex lens of focal length 30 cm in contact with a concave lens of focal length 20 cm, if they are placed 8.0 cm apart with their principal axes coincident. An object 1.5 cm in size is placed on the side of the convex lens. The distance between the object and the convex lens is 40 cm. Determine the magnification produced by the two-lens system, and the size of the image.

Write expression for the rate of decay.

Write expression for power factor.

Write expression for Boyle's law.

Write an expression for the frequency produced by a stretched string.

Write expression for Charles's law.