Sound — Science STD 9 — Question

Remains of heavy metals like lead, arsenic, cadmium, etc. from mines are industrial waste.

Japan is the largest producer of electricity from solid waste.

Forecasting is difficult for places where climatic changes are slow and of a limited nature.

State whether the following statements are true or false:
'Archimedes’ principle can also be applied to gases.

Certain plastic bags take 1 month to degrade.

State whether the following statements are true or false:
A sodium ion has positive charge because it has more protons than a neutral atom.

The following statements are true or false:
The acceleration due to gravity acting on a freely falling body is directly proportional to the mass of the body.

We should use tissue paper instead of one’s own handkerchief for effective waste management.

Climate plays a very important role in the formation and enrichment of soil.

The following statements are true or false:
The force of gravitation between two objects depends on the nature of medium between them.