The M of a sheet of metal varies with it area A and it thickness T. If a sheet of metal ,of area 250cm^2 and thickness 1mm has a mass of 200gm .
Find the law connecting M,A and T.
Find the formula in A that makes A the subject of the formula.
Hence ,find A where M =950gm and T=3mm
M = k * Volume = k * T * A
200 g = k * 1 mm * 250 cm^2
k = 0.8 g / mm cm^2
so
A = M /(0.8 T) = 1.25 M/T
= 1.25 * 950 / 3
= 396 cm^2
or area up with mass and down with thickness
A2 = A1 M2/M1 T1/T2= 396 again