As soon as current is switched on in a high-voltage wire, the bird sitting on it flies away, why?

A stone tied at the end of sring is whirled in a circle. If the string break , the stone flies away tangentially . Why ?

A wire is stretched between two bridges A and B. A small piece of paper of shape A (called rider) is placed at the middle of the wire. When the stem of a tuning fork P is placed at the bridge A the rider only vibrates, but it flies away when another tuning fork Q is placed. Explain the difference.

A bird is sitting on the floor of a wire cage and the cage is in the hand of a boy . The bird starts flying in the cage . Will the boy experience any change in the weight of the cage ?

A square loop of side a is placed at a distance a length away from a long wire carrying a current I_1 . If the loop carries a current I_2 as shown in the figure . Then the nature of the nature of the force and its amount is

A straight peice of conducting wire with mass M and length L is placed on a frictionless incline tilited at an angle theta from the horizontal (as shown in fig) There is a uniform. Vertical magnetic field at all points (produced by an arrangement of magnets not shown in fig. To keep the wire from sliding down the incline, a voltage source is attached to the ends of the wire. When just the right amount of current flows through the wire, the wire remains at rest. Determine the magnitude and direction of the current in the wire that will cause the wire to remain at rest.

A bird is sitting on the top of an 80 m high tree. From a point on the ground, the angle of elevation of the bird is 45^(@) . The bird flies away horizontally in such a way that it remained at a constant height from the ground. After 2 seconds, the angle of elevation of the bird from the same point is 30^(@) . Find the speed of flying of the bird. (Take sqrt3=1.732 ).

A bird flies with a speed of 10 km/h and a car moves with uniform speed of 8 km/h. Both starts from B towards A (BA = 40 km), at the same instant. The bird having reached A, flies back immediately to meet the approaching car. As soon as it reaches the car it flies back to A. Thus the bird repeats till both the car and the bird reach A simultaneously. The total distance flown hy the bird is [see Fig. 3.7]

Find the current in each wire applying only Kirchhoff voltage law

Resistance of a given wire is obtained by measuring the current flowing in it and the voltage difference applied across it. If the percentage errors in the measurment of the current and the voltage difference are 3% each, then error in the value of resistance of the wire iS :

A generator at a utility company produces 100 A of current at 4000 V. The voltage is stepped up to 240000 V by a transformer before it is sent on a high voltage transmission line. The current in transmission line is