Physics
The diagram shows a coil wound around a U shape soft iron bar AB.
(i) What is the polarity induced at the ends A and B when the switch is pressed?
(ii) Suggest one way to strengthen the magnetic field in the electromagnet.
(iii) What will be the polarities at A & B if the direction of current is reversed in the circuit?
Answer
(i) The polarity induced at the end A is North and at the end B is South.
(ii) To strengthen the magnetic field in the electromagnet, the current flowing in it is increased.
(iii) On reversing the direction of current, the end A will be south pole and the end B will be the north pole.
Related Questions
Radiations given out from a source when subjected to an electric field in a direction perpendicular to their path are shown in the diagram. The arrows show the path of the radiation A, B and C. Answer the following question in terms of A, B and C.
(i) Name the radiation B which is unaffected by the electrostatic field.
(ii) Why does the radiation C deflect more than A?
(iii) Which among the three causes the least biological damage externally.
(iv) Name the radiation which is used in carbon dating.
The temperature of 170 g of water at 50°C is lowered to 5°C by adding a certain amount of ice to it. Find the mass of ice added.
Given: Specific heat capacity of water = 4200 J kg-1 ⁰C-1 and Specific latent heat of ice = 336000 J kg-1
(i) State two differences between "Heat Capacity" and "Specific Heat Capacity".
(ii) Give a mathematical relation between Heat Capacity and Specific Heat Capacity.