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An ellipse is described by using an endless string which is passed over two pins. If the axes are 6 cm and 4 cm long, the length of the string and the distance between the pins are respectively……………..

The lengths of two sides of a triangle are 6 cm and 8 cm. Between which two numbers can length of the third side fall?

A pair of parallel horizontal conducting rails of negligible resistance shorted at one end is fixed on a table. The distance between the rails is L. A conducting massless rod of resistance R can slide on the rails frictionlessly. The rod is tied to a massless string which passes over a pulley fixed to the edge of the table, A mass m, tied to the other end of the string hanges vertically. A constant magnetic field B exists perpendicular to the table. If the system is released from rest, calculate. the terminal velocity achieved by the rod.

A pair of parallel horizontal conducting rails of negligible resistance shorted at one end is fixed on a table. The distance between the rails is L. A conducting massless rod of resistance R can slide on the rails frictionlessly. The rod is tied to a massless string which passes over a pulley fixed to the edge of the table, A mass m, tied to the other end of the string hanges vertically. A constant magnetic field B exists perpendicular to the table. If the system is released from rest, calculate. the acceleration of the mass at the instant when the velocity of the rod is half the terminal velocity.

A piece of string is 30 cm long.What will be the length of each side if the string is used to form: a square?

Two circles of radii 5 cm and 3 cm intersect at two points and the distance between their centres is 4 cm. Find the length of the common chord.

Two small charged metal sphere A and B are situated in a vaccum. The distance between the centres of the spheres is 12.0 cm, as shown in the fig. The charge on each sphere may be assumed to be a point charge at the centre of the sphere. Point P is a movable point that lies on the line joining the centres of the sphere and is distance x fromt he centre of sphere A. The variation with distance x fo the electric field strength E at point P as shown in the figure. Use fig to state and explain the distance x at which the rate of change of potential with distance is maximum and minimum.

The lengths of two parallel chords of a circle are 6 cm and 8 cm. If the smaller chord is at a distance of 4 cm from the centre, what is the distance of the other chord from the centre ?

A transverse harmonic wave on a string is described by y(x. t) = 3.0 sin (36 t + 0.018 x + (pi//4)) where x and y are in cm and tin s. The positive direction of x is from left to right. What is the least distance between two successive crests in the wave ?

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.