Question

the mass of a uniform copper bar varies directly as it's length.if a bar 40cm long has a mass approximately 420g, find the mass of a bar 136cm long​

Answer 1

Let the mass be x

Mass = 420,x

Length =40,136

So using unitary method:

40x=420×136

X=420×136/40

x=1428g

Therefore,the mass of the bar 136cm long is 1428 g