Question

19 Read the following and answer any four questions from 19 (i) to 19 (v)

One student take a small aluminium rod AB ( about 5.0cm) . Using two

connecting wires suspend it horizontally from a stand , as shown in figure.

Place a strong horse- shoe magnet in such a way that the rod lies between the

two poles with the magnetic field directed upwards. For this put the north pole

of the magnet vertically below and south pole vertically above the aluminium

rod. Connect the aluminium rod in series with a battery, a key and a rheostat

and pass the current through the aliminiumrod from end B to Ait is observed

that the rod is displaced towards the left. Reverse the direction of current

flowing through the rod and observe the direction of its displacement. It is

now towards the right.19 (i) Based on the diagram shown, if magnitude of current flowing in the aluminium

rod increases . What can you say the displacement of the rod.

a) Displacement of the rod decreases

b) No change the displacement of the rod

c) Displacement of the rod increases

d) We can’t say anything.

19 (ii) Which rule are we using to determine the direction of force acting on

aluminium rod?

a) Right hand rule

b) Fleming’s right hand rule

c) Ampere’s swimming rule

d) Fleming’s left hand rule

19 (iii) Which device is working on the principle of explaining in given activity.

a) Generator

b) Electric motor

c) Bulb

d) Heater

19 (iv) A positive – charged particle ( alpha particle) projected towards west is

deflected towards north by a magnetic field. The direction of the magnetic field

is

a) Towards south

b) Towards east

c) Downward

d) Upward

19 (v) In activity, how do you think the displacement of rod AB will be affected if

stronger horse- shoe magnet is used and length of the rod is also increased.

a) No change

b) Increases

c) Decreases

d) May be increases and decreases​

Answer 1

Answer:

c) Decreases

(b) Towards east