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How does an electrical impulse travel the gap between two nerves?

The electrical impulse that travels along a nerve, known in biology as an action potential, gets passed along to an adjacent nerve as a chemical signal. When an action potential reaches the end of a nerve...

Answered by Lucy M. • Biology tutor

5016 Views

a sample of hydrated NiSO4 witha mass of 4.414g is heated to remove all water crystallisation. The resultant mass is 2.287g. How many H2O molecules to each NiSO4 were there in the original sample

Mr of NiSO4 is 154.8 g/mol Mr of H2O is 18

Mass of NiSO4 in sample is 2.287 g Mass of H2O in sample is 4.414-2.287 = 2.127g

divide mass of each of NiSO4 and H2O by Mr to obtain the ratio in ...

Answered by Calum S. • Chemistry tutor

3448 Views

Is there such a thing as pure, rational knowledge? Would mathematics fall into this category?

This is a classic epistemological question asking you to engage with the debate between rationalists like Descartes and empiricists like Hume. To answer this effectively we need to make clear what the opp...

Answered by Tom R. • Philosophy tutor

2780 Views

calculate the resistivity in a 1.2m length of cylindrical wire with radius 1cm. The resistance of the wire is 0.01 kilo Ohms

The primary equation in this calculation is rho = RA/L Where rho is resistivity, A is cross sectional area, L is length, and R is resistance

The resistance and length are given in the question. Res...

Answered by Calum S. • Physics tutor

3709 Views

What is the first derivative of y=5z(1+2z2)? Is this a minimum, maximum or turning point?

You should not be put off by the algebraic letters used, substituting x's for z's is absolutely fine. For the first part of the question, since the equation involves the product of two terms, there are tw...

Answered by Tom R. • Maths tutor

4145 Views