Physics
The diagram below shows a magnetic compass kept closer to a coil AB wound around a hollow cylindrical cardboard :
(a) After studying the circuit and the magnetic compass carefully, state whether the switch S1 is open or closed.
(b) How did you arrive at the conclusion in (a)?
(c) What is the purpose of placing the magnetic compass in the above setup?
Answer
(a) The switch S1 is closed.
(b) When the key is pressed, a current passes in the wire in the direction from A to B (i.e. from south to north) and the north pole (N) of the needle deflects towards the west. There is a deflection in the magnetic compass. So, it is concluded that the switch S1 is closed and current is flowing through the coil.
(c) The purpose of placing the magnetic compass is to determine the polarity developed at the end A of the solenoid.
Related Questions
In the below circuit diagram, calculate:
(a) the external resistance of the circuit.
(b) the current I2.
(c) the current I.
Three wires with proper colour coding are connected to the three terminals of a three-pin socket. Match the colour of the wire with the proper terminals A, B and C of the socket.
(a) Brown
(b) Green
(c) Light blue
(a) Why does it become colder after a hailstorm than during or before the hailstorm?
(b) 'If two bodies have the same specific heat capacities, then they will always absorb the same amount of heat if their temperature increases by the same amount.' State whether the given statement is true or false.
(a) Give an important reason for copper to be used as a material for a calorimeter.
(b) Calculate the thermal capacity of 40 g of water.
[Specific heat capacity of water = 4200 JKg-1°C-1]