(a) Negative values for *R* have no physical
significance, hence *P* is not plotted for negative values
of *R.*

(b) Draw up a table of values:

R |
0 | 1 | 2 | 3 | 4 | 5 |

P |
0 | 44.4 | 32.0 | 24.5 | 19.8 | 16.5 |

(c) Check what happens between `R = 0` and `R = 1` ie.

when `R = 0.25`, `P = 44.4`

`R = 0.50`, `P = 50 ``R = 0.75`, `P = 48`

Note the axes are labelled with *R* (resistance) and *P* (power).

(d) Conclusions:

(i) The maximum power of `50\ "W"` occurs when resistance `R = 0.5\ "W"`

(ii) *P* decreases as *R* increases beyond `0.5\ "W"`

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