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Use your knowledge of the humoral immune response to explain a vaccination programme

Interesting topic with regards to COVID-19A vaccine introduces a foreign pathogen into the body. This foreign body stimulates the innate immune response which occurs regardless. The process of phagocytosis o...
WA
Answered by Will A. • Biology tutor
3941 Views

How does the subjunctive work in Spanish?

The subjunctive is used in Spanish to present possibility - something that isn't certain. For example, if I'm not sure if it will rain or not, I would say 'Es posible que lluvie' (It is possible that it will...
MP
Answered by Marina P. • Spanish tutor
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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
EM
Answered by Elliott M. • Physics tutor
1841 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 one...
BJ
Answered by Becky J. • Chemistry tutor
11120 Views

Please describe the structure of atom, with reference to the relative mass and charge.

At the centre of the atom, is the nucleus. This is made up of protons and neutrons. Protons are positively charged, with a relative charge of +1. Whilst neutrons are neutral (relative charge = 0).Surrounding...
EM
Answered by Elliott M. • Physics tutor
3353 Views