A guy wire attached to a vertical pole of height 18 m is 24 m long and has a stake attached to the other end. How far from the base of the pole should the stake be driven so that the wire will be taut ?

A circus artist is climbing a 20m long rope, which is tightly stretched and tied from the top of a vertical pole to the ground. Find the height of the pole, if the angle made by the rope with the ground level is 30^@ (see fig.).

Two equal and unlike poles placed 5cm apart in air attract each other with a force of 14.4times10^(4) N.How far from each other should they be placed so that the force of attraction will be 1.6times10^(4)N .

The cable of a uniformly loaded suspension bridge hangs in the form of a parabola. The roadway which is horizontal and 100 m long is supported by vertical wires attached to the cable, the longest wire being 30 m and the shortest being 6 m. Find the length of a supporting wire attached to the roadway 18 m from the middle.

The cable of a uniformly loaded suspension bridge hangs in the form of a parabola. The roadway which is horizontal and 100 m long is supported by vertical wires attached to the cable, the longest wire being 30 m and the shortest being 6 m. Find the length of a supporting wire attached to the roadway 18m from the middle.

The number density of free electrons in a copper conductor estimated in Example 3.1 is 8.5 xx 10^28 m^-3 . How long does an electron take to drift from one end of a wire 3.0 m long to its other end? The area of cross-section of the wire is 2.0 xx 10^-6 m^2 and it is carrying a current of 3.0 A.

A long horizontal rigidly supported wire carries a current i_a of 100 A. Directly above it and parallel to its is a fine wire that carries a current i_b of 20 A and weighs 0.073 N/m. How far above the lower wire should the second wire be kept if we wish to support it by magnetic repulsion? Given permeability constant mu_0= 4pi xx 10^-7 Wb A^-1m^-1 .

Nazima is fly fishing in a stream. The tip of her fishing rod is 1.8 m above the surface of the water and the fly at the end of the string rests on the water 3.6 m away and 2.4 m from a point directly under the tip of the rod. Assuming that her string (from the tip of her rod to the fly) is taut, how much string does she have out ? If she pulls in the string at the rate of 5 cm per second, what will the horizontal distance of the fly from her after 12 seconds ? .

The two parallel circular loops of wire shown in fig each have a radius R = 20 cm and are separated by a distance a = 0.5 cm. The bottom loop is held fixed and the top loop hangs from one end of the arm of an equal arm balance. Since a is much smaller than R, the magnetic field produced by one loop at the other is practically the same as if both were long straight wires. if the current in each loop is 20 A. How much additional mass m must be added to the right-hand pan of the balance to keep the loops separated by 0.5 cm, when the currents are turned on?