Motion and Time — Science STD 7 — Question

Which of the two absorbs more radiation a dark coloured object or a light coloured object?

Give two examples of natural fibres.

Note the changes in shape, size or state : Chopping vegetables

Name the gas that turns lime water milky.

Name the device on vehicles to track the distance covered.

If there were fewer trees, how will the water cycle be affected?

Y and Z are two types of organisms which are found in the forests. Y eats up dead animals, while Z breakdown the body of the dead animals into simpler substances.
(a) What is the general name of organism Y?
(b) Write one example of Y type organism.
(c) What is general name of organism Z?
(d) Write one example of Z type organism.

Name the organism responsible for converting atmospheric nitrogen into soluble forms.

A food stall owner was preparing dough for making bhaturas. He added a pinch of yeast and sugar to the dough and left it in a warm place. After few hours, the dough had risen. There was a sour smell too.
Why did the dough rise?

What happens when a partially inflated balloon is placed in the Sun?