1. State one limitation of solar energy available from solar cells

[AmarCBSE]

1. State one limitation of solar energy available from solar cells.
2. What is the minimum wind velocity required to obtain useful energy with a windmill?
3. Define the term ‘nuclear fission’.

[AmarCBSE]

1. The solar cells are costly and hence, the energy available from them is expensive.
2. 15 km/h is the minimum wind velocity required to obtain useful energy with a windmill.
3. Nuclear fission is the process in which a radioactive atom splits up into smaller nuclei when struck with low energy neutrons.