Question

The mass of a solid iron cube of side 3cm is to be determined using a spring balance.If the density of iron is approximately 8.5 g / cm ^ 3, the best suited spring balance for determining the weight of the solid would be of: (a)Range 0-250gwt;Least Count 1gwt (b)Range 0-250gwt;Least Count 5 gwt (c)Range 0-1000gwt;Least Count 5 gwt (d)Range 0-1000gwt;Least Count 10 gwt Answer with reason please.

Answer 1

It will be (d) as it will best suit to measure its mass.

Answer 2

Edge of the cube , a = 3 cm

Volume of a cube = a³ = 3³ =27 cm³


Density = 8.5 g/cm³


Density = $\frac{Mass}{Volume}$

Mass = Density x Volume
= 8.5 x 27
= 229.5 grams

So , (a)spring balance with range 0-250 gwt ; least count 1gwt will be suitable .