The area of a triangle is measured in terms of b, c, A If A = 63^º and there is an error of 15 in A, the percentage error in the area is

The point on the ellipse 16x² + 9y² = 400 where ordinate decrease at the same rate at which the abscissa increases is

For such questions, we should know how to find the derivates. We should know the concept of abscissa and ordinate.

The displacement of a particle in time ‘t’ is given by S = t³ – t² – 8t – 18. The acceleration of the particle when its velocity vanishes is

For such questions, we should know relation between displacement, velocity and time. We should also know how to find first and second order derivate.

If and then is equal to

The figure shows a transparent slab of length 1 m placed in air whose refractive index in x direction varies as . The optical path length of ray R will be

A parallel beam of light 500 nm is incident at an angle 30° with the normal to the slit plane in a young's double slit experiment. The intensity due to each slit is Io. Point O is equidistant from and . The distance between slits is 1 mm.

In a Young's Double slit experiment, first maxima is observed at a fixed point P on the screen. Now the screen is continuously moved away from the plane of slits. The ratio of intensity at point P to the intensity at point O (centre of the screen)

An YDSE is carried out in a liquid of refractive index and a thin film of air is formed in front of the lower slit as shown in the figure. If a maxima of third order is formed at the origin O, find the thickness of the air film. The wavelength of light in air is and D/d=1000.

Two coherent radio point sources that are separated by 2.0 m are radiating in phase with a wavelength of 0.25 m. If a detector moves in a large circle around their midpoint, at how many points will the detector show a maximum signal ?

Two coherent narrow slits emitting light of wavelength in the same phase are placed parallel to each other at a small separation of . The light is collected on a screen S which is placed at a distance from the slit as shown in figure. Find the finite distance x such that the intensity of P is equal to intensity at O.

Consider the arrangement shown in figure. By some mechanism, the separation between the slits and can be changed. The intensity is measured at the point P which is at the common perpendicular bisector of and . When , the intensity measured at P is I. Find this intensity when z is equal to

1) ,
2) , and
3) .

In Young's double slit experiment and are two slits. Films of thicknesses and and refractive indices and are placed in front of and respectively. If , then the central maximum will :

Two coherent sources are placed 0.9 mm apart and the fringes are observed one metre away. The wavelength of monochromatic light used if it produces the second dark fringes at a distance of 10 mm