Question

Q.15 A heater rated 250W is connected to 220V supply. Calculate (i) resistance of the heater and

(ii) current flowing through the heater

2

Q.16 State the law which governs the amount of heat produced in a metallic conductor when

electric current is passed through it for a given time. Express this law mathematically.

2

Q.17 Enlist different parts of nephron and their functions. 3

Q.18 (a) Why do organisms reproduce?

(b) Draw well labelled diagram of human female reproductive system

3

Q.19 Write a balanced chemical equation for each of the following reactions and also classify

them.

(a) Lead acetate solution is treated with dilute hydrochloric acid to form lead chloride and

acetic acid solution.

(b) A piece of sodium metal is added to absolute ethanol to form sodium ethoxide and

hydrogen gas.

(c) Magnesium reacts with nitric acid to form magnesium nitrate, ammonium nitrate and

water.

3

Q.20 A metal carbonate X on reacting with an acid gives a gas which when passed through a

solution Y gives the carbonate back. On the other hand, a gas G is obtained at anode during

electrolysis of brine is passed on dry Y, it gives a compound Z, used for disinfecting drinking

water. Identify X, Y, G & Z. & also write all chemical reactions while formation of X, Y, G

& Z in the above.

3

Q.21 State the law which governs the strength of the current passing through a metallic conductor

when a potential difference is applied across its ends. Illustrate this law graphically.

Three resistors each of resistance 10 ohm are connected in turn, to obtain

(i) Minimum resistance (ii) maximum resistance Compute

(a) The effective resistance in each cases

(b) The ratio of minimum to maximum resistance so obtained.

3

Q.22 A concave lens of focal length 20cm, form an image at a distance of 10 cm from the lens.

What is the distance of the object from the lens? Also draw ray diagram.


please say me fast​

Answer 1

Answer:

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