Question

a cylindrical road-roller made of iron is 1 m wide .ITs inner diameter is 54 cm and thickness of the iron sheet rolled into the road roller is 9 cm. Find the weight of the roller if 1 cc of iron weights 8gms. the ans. is 1601.6....plzz solve it fast

Answer 1

Let r and R be the inner and outer radius if the cylindrical road roller respectively.

R = Inner radius if the cylinder + Thickness of the iron sheet = 27 cm + 9 cm = 36 cm

Volume of iron in the road roller

= π (R2 – r2) h

Given, weight of 1 cm3 of iron = 7.8 gm

∴ Weight of 178200 cm3 of iron = 7.8 × 178200 gm = 1389960 gm = 1389.96 kg

Thus, the weight of the road roller is 1389.96 kg.

And this is the correct answer which is checked by R.D Sharma! Hope this helps!