Physics Questions

Hydroelectricity is electricity produced from hydropower i.e, water.

The lux (lx) is the SI derived unit of illuminance and luminous emittance, measuring luminous flux per unit area. It is equal to one lumen per square meter.

Newton's III law involved

This is a layer of atmosphere about 60 to 70 km above the earth and extends to about 400km. It contains ionised particles which can reflect radio waves making radio communication round the world possible.

The eye can see images separately only if they are exhibited at an interval of more than 1/10 of a second. In the case of a movie, the still pictures come one after the other at less than this minimum interval. So we do not see them separately but only as a continuous moving picture.

As the inside of the cooker is painted black, heat absorption is more producing heat waves of longer wavelength which cannot escape through glass and hence are trapped inside. Thus the food is cooked.