Except for the following questions, all the remaining questions. have been asked in Set I and Set II.

**Q. 1.** A cylinder of a material is 10 cm long and has a cross-section of 2 cm^{2} If its resistance along the length be 20 ohms, what will its resistivity value be in number and units?** 1**

**Q. 2.** The focal lengths of lenses used as objective and eye-piece in a telescope are respectively 1 m and 1 cm. What will be the distance between the two lenses if the telescope is set for normal adjustment position? **1**

**Q. 3.** What is denatured alcohol?** 1**

**Q. 6.** State how we can locate the pole star in the sky. **2**

**Q. 10. **An electric appliance draws a current of 0.4 A when the. voltage is 220 volts. Calculate the amount of electric charge flowing through it in one hour. **2**

**Q. 11.** An object 3 cm high is placed at a distance of 24 cm in front of a convex lens of focal length 16 cm. Find the position, nature and size of the image formed. **3**

Or

An object 4 cm high is placed at a distance of 6 cm in front of a concave mirror of focal length 12 cm. Find the position, nature and size of the image formed.

**Q. 19.** a) Express Ohm’s law by a mathematical formula.

b) Draw a circuit diagram to verify Ohm’s law.

c) Present the relationship between the voltage applied across a conductor

and the current flowing through it graphically. **1, 2, 2**

**Q. 22. **Name the scientist who proposed the theory of natural selection.**1**

Science 2004 Question Papers Class X

CBSE 2004 Question Papers Class X