T2 CH1 Heat and Temperature — Science STD 7 — Question

HOTS
Silk fiber is used to manufacture parachute. Why?

Define molecule.

Define Isobars. Give example.

Rajan was playing with the mirror images of a clock. He looked at the clock in his room. It was showing 1:40. Draw the position of the hands on the real clock and on its mirror reflection. Write below the picture what time each picture is showing.

What is slow combustion? Give example.

Why is it better to avoid the use of plastic products?

Describe the pictures.
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Higher Order Question
A student made a circuit by using an electric cell, a switch, a torch bulb (fitted in the bulb holder), and copper connecting wires. When he turned on the switch, the torch bulb did not glow at all. The student checked the circuit and found that all the wire connections were tight.

• What could be the possible reason for the torch bulb not glowing even when the circuit appears to be complete?

Give two example of elements.