A straight wire of length 30 cm and mass 60 mg lies in a direction `30^(@)` east of north.The earth's magnetic field at this is horizontal and has a magnitude of 0.8 G.What current must bre passed through the wire,so that it may float in air ?

A straight wire of mass 400 g and length 2m carries a current of 2A. It is suspended in mid air by a uniform horizontal field B. What is the magnitude of the magnetic field ?

A straight wire of mass 200 g and length 1.5 m carries a current of 2 A. It is suspended in mid-air by a uniform horizontal magnetic field B. What is the magnitude of the magnetic field?

A wire of 60 cm length and mass 16 gm is suspended by a pair of flexible leads in a magnetic field of induction 0.40 T. What are the magnitude and direction of the current required to remove the tension in the supporting leads?

A current of 5.0 A exists in the circuir shown in The wire PQ has a length of 50 cm the magnetic field in which it is immersed has a magnitude of 0.20 T. Find the magnetic force acting on the wire PQ.

A straight wire having mass of 1.2 kg and length of 1m carries a current of 5 A. If the wire is suspended in mid-air by a uniform horizontal magnetic field, then the magnitude of field is

A straight wire of length 50 cm carrying a current of 2.5 A is suspended in mid-air by a uniform magnetic field of 0.5 T (as shown in figure). The mass of the wire is (g = 10 ms^(-2) )

A long straight wire carrying current of 30 A is placed in an external uniform magnetic field of induction 4xx10^(4) T . The magnetic field is acting parallel to the direction of current. The magnitude of the resultant magnetic inuduction in tesla at a point 2.0 cm away form the wire is