Question

Mandy works construction. She knows that a 555 meter long metal bar has a mass of 40 \text{ kg}40 kg40, start text, space, k, g, end text. Mandy wants to figure out the mass (w)(w)left parenthesis, w, right parenthesis of a bar made out of the same metal that is 333 meters long and the same thickness. What is the mass of the shorter bar?

Answer 1

Answer:

24 kg

Step-by-step explanation:

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Answer 2

Answer:

The mass of the bar of length 333m made of same material and having same thickness is 24kg.

Step-by-step explanation:

Given:

Length of the metal bar = 555m

Weight of the metal bar = 40kg

Let this be B₁

To find:

The weight of 333m same metal bar having same thickness

Let this be B₂

We know:

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

Volume = Area * Length

Solution:

As the metal bar whose weight is to be calculated is made of the same material => the density of both the metal bars is equal

Also we know that both the bars have same thickness => the area of cross section of both the metal bars is equal

=> Density of B₁ = Density of B₂

=> $\frac{40}{Area * 555}$ = $\frac{Mass}{Area*333}$          

=>  $\frac{40}{555}$ = $\frac{Mass}{333}$                                         (as area is equal)

=>  $\frac{40}{5}$ = $\frac{Mass}{3}$

=> Mass = 24kg

Therefore, the mass of the bar of length 333m made of same material and having same thickness is 24kg.