Nuclear fuel is a material that can be used to produce nuclear energy through fusion or fission. Naturally occurring nuclear fuel is uranium, which is mostly U-238 but also contains small amounts of U-235 and U-234. Additional fissionable materials like Pu-239 and U-233 can be artificially produced from U-238 and Th-232. Nuclear fuel is considered efficient if it produces a large amount of energy while generating only a small amount of pollutants.

2. NUCLEAR FUEL is a material which can be
used or consumed by nuclear fusion or fission to
derive NUCLEAR ENERGY

3. The only Fissionable nuclear fuel occurring in
nature is URANIUM , of which is 99.3% U-238
and 0.7% is U-235 and U-234 is only a trace.
The other fissionable materials are Pu-239
and U-233 which can be produced artificially
from U-238 and Th-232.

4. NUCLEAR FUEL IS SAID TO BE
EFFICIENT IF IT PRODUCES A
LOT OF ENERGY AND A VERY
SMALL BIT OF POLLUTANT.