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What is the difference between velocity and speed?

Both the speed and the velocity show us how fast something is moving (the rate at which it changes its position). However, velocity is a vector quantity, which means it also gives us information about the di...
BS
Answered by Bozhidara S. • Physics tutor
3499 Views

Describe how you could find the density of a cube of metal? (4 marks) (Example from GCSE bitesize)

Think of key words in the questions to help solve it. For example in this question we need to consider density and the fact that the object is a cube. 2) Remember the equation of density which is : Density =...
BA
Answered by Branwen A. • Physics tutor
4519 Views

Explain how the central bank can change interest rates to manipulate Aggregate Demand.

The key concept here is that interest rates essentially represent the price of money. The central bank sets the interest rate to loan to high-street banks, and the high-street banks follow this guidance to s...
ML
Answered by Matt L. • Economics tutor
2332 Views

What is the 'lock and key' hypothesis?

A reaction can only be catalysed (sped up) if an enzyme's active site matches the shape of its substrate molecules- the substrate fits into the active site like a key into a lock. This shape is highly specif...
EE
Answered by Emily E. • Biology tutor
3154 Views

Calculate the empirical and molecular formula of unknown compound A which gave an m/z of 181 in the mass spectrum for the molecular ion peak. Elemental analysis by combustion shows the compound is C 53%, O 35.4%, H 3.9% and N 7.7%.

C atomic mass -12 C percentage by composition : 53% Atomic ratio of C : 53/12= 4.417 H atomic mass -1 H percentage by composition : 3.9% Atomic ratio of H : 3.9/1=3.9 N atomic mass - 14 N percentage by compo...
AS
Answered by Aminat S. • Chemistry tutor
3811 Views