Physical and Chemical Changes — Science STD 7 — Question

What is the thin wire inside an incandescent lamp called?

Name the phenomenon that is involved in the formation of image of an object by a concave mirror.

Which indicators change odour with different substances?

When the opaque object was a shiny object like a polished steel plate, I got a shadow on the screen, but I also saw that there was a bright spot of light on the wall on the opposite side. Why was it so?

How do you define heat flow?

Why can water move through gravel more easily?

Some definitions are given below which can be corrected by changing one word. Correct them: The evaporation of water from oceans and its arrival back into oceans is called vapour cycle.

Did chlorine have an odour? Was it worse than that of the wastewater?

What is shadow? How does the colour of an opaque object affects the colour of the shadow?

Which type of soil absorbs more water but allows less wateMo percolate?