Electricity: Circuits and their Components — Science STD 7 — Question

Explain what happens when the switch is OFF.

Can we contribute in sanitation at public places? Explain.

How can a pipal sapling would have grown on a side wall of some old buildings?

If we never questioned existing ideas, how would that impact scientific progress?

Look at the figure given below and answer whether the compass needle will show deflection or not when the switch in the circuit shown is closed?

Define combustion. What are the prerequisite conditions for the combustion reaction to occur.

Suggest materials for a new building which are resistant to corrosion.

Shalu told her friend, “Adolescence brings only physical changes, like growing taller or developing body hair. ” Is she correct? What would you change in this description of adolescence?

Suppose the ‘+’ and symbols cannot be read on a battery. Suggest a method to identify the two terminals of this battery.

For setting curd, a small amount of curd is added to warm milk. The microbes present in the curd help in setting if the temperature of the mixture remains approximately between 35°C to 40°C. At places, where room temperature remains much below the range, setting of curd becomes difficult. Suggest a way to set curd in such a situation.