Heat — Science STD 7 — Question

What are stomata? Give two functions of stomata.

How can we compare the speeds of two objects to determine which one is moving faster?

Analyse why sulphur cannot be used to prevent rusting.

Name the different types of graphs.

The Moon is much smaller than the Sun, yet it can block the Sun completely from our view during a total solar eclipse. Why is it possible?

Boojho saw an ambulance on the road. He was surprised to see the word 'AMBULANCE' in front was written in a strange manner. Why?

If current is passed through a coil, does the pins cling to the coil?

Design a way to record time using only shadows and a stick.

Boojho wonders if sponges and Hydra also have blood?

Pick the odd-one-out from each of the groups given below on the basis of respiratory organs. Give reason for your answer.
(a) cockroach, grasshopper, snail, ant
(b) lizard, cow, earthworm, snake
(c) crocodile, whale, dolphin, fish
(d) snake, tadpole, crow, goat