When an iron rod is dipped into a solution of copper sulphate, copper is displaced. Why is it so?

Draw ray diagrams to show the formation of a three times magnifier (i) real image (ii) virtual image of an object kept in front of a converging lens. Mark the positions of object, F, 2F, O and position of image clearly in the diagram.

An object of size 5 cm is kept at a distance of 25 cm from the optional centre of a converging lens of focal length 10cm. Calculate the distance of the image from the lens and size of the image.

A current of 1 ampere flows in a series circuit having an electric lamp and a conductor of 5 ohm when connected to a 10 V battery. Calculate the resistance of the electric lamp.

Now if a resistance of 10 ohm is connected in parallel with this series combination, what change (if any) in current flowing through 5 ohm conductor and potential difference across the lamp will take place? Give reason.

OR

B₁, B₂, B₃ are three identical bulbs connected as shown in the figure. Ammeters A₁, A₂, A₃ are connected as shown. When all the bulbs glow, the current of 3A is recorded by ammeter A.

i. What happens to the glow of the other two bulbs when bulb B₁ gets fused?

ii. What happens to the reading of A₁, A₂, A₃ and A when the bulb B₂ gets fused?

iii. How much power is dissipated in the circuit when all the three bulbs glow together?

Iron filings were added to a solution of copper sulphate. After 10 minutes, it was observed that the blue colour of the solution changes and a layer gets deposited on iron filings. What is the colour of the solution and the layer deposited?

While preparing a temporary stained mount of an epidermal leaf peel, how is the extra stain removed?