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If a 10N tension force is exerted on a steel beam (E = 200 GPa) with cross-sectional area 1cm^2, what is the stress acting on the beam? What is the change in length of the beam, if the beam is 10cm long?

F = 10NA = 1x10^-6 m^2Therefore, Stress = 10 MPaStrain = Stress / E = 10 / 200 x10^3 = 5x10^-5 delta L = strain x length = 5x10^-4 cm = 5 micrometers

Answered by Elliott M. • Physics tutor

1161 Views

What is the difference between empirical and molecular formula?

The molecular formula of an atom shows you the actual number of atoms of the elements in a compound. For example ethane has molecular formula C2H6 meaning there are 2 carbon atoms and 6 hydrogen atoms in ...

Answered by Becky J. • Chemistry tutor

7815 Views

Cells need mRNA molecules to create proteins. How are they created?

Protein synthesis is a convoluted process but, essentially, all the cell is doing is 'reading' the instructions contained within the base sequence in the correct gene or 'section' of the DNA and then doin...

Answered by Matthew J. • Biology tutor

2389 Views

How does Hardy's 'Tess of the D'Urbervilles' reflect the attitudes of the era?

The subtitle of the novel 'A Pure Woman Faithfully Presented' represents Hardy's moral view of Tess in contrast to the Victorian attitudes of the characters around her.
The novel generally follows t...

Answered by louise r. • English Literature tutor

6531 Views

Find the area under the curve with equation y = 5x - 2x^2 - 2, bounded by the x-axis and the points at which the curve reach the x-axis.

First, we must find the two points at which the curve crosses the boundary. To do this, set y=0 and solve.0 = 5x - 2x² - 20 = (2x - 1)(-x+2)This gives that x = 0.5 and x = 2Next, we integrate w...

Answered by Natassja K. • Maths tutor

3291 Views