Part A
Weight of a piece of wire is directly proportional to its length
⇒ Weight of wire piece (W) α Length of wire (L)
⇒ W = k × L
When L = 25 cm, then W = 6 gms
⇒ [tex]\frac{W}{L}[/tex] = k
⇒ k = [tex]\frac{6}{25}[/tex]
To calculate weight of 30 cm wire, put value of k and W in the expression W = k × L
⇒ W = [tex]\frac{6}{25}[/tex] × 30
⇒ W = 7.2 gms
Part B
p α m
⇒ p = k × m
If p=48 and m=9
k = [tex]\frac{p}{m}[/tex]
⇒ k = [tex]\frac{48}{9}[/tex]
Now to calculate p when m = 12, substitute the value of m and k in p = k × m
p = [tex]\frac{48}{9}[/tex] × 12
⇒ p = 64
