Top answers

Why do all objects fall at the same rate in a vacuum, independent of mass?

This is only the case in a vacuum because there are no air particles, so there is no air resistance; gravity is the only force acting. You can see it for yourselves with this easy experiment: Take one piece ...
LT
Answered by Luke T. • Physics tutor
88734 Views

What are different animal's cognitive limitations? How can we observe this in the wild?

There is obviously no black and white answer, but the study of behavioural ecology tackles this issue. Empirical studies in the animal's natural environment are more difficult but more rewarding to conduct t...
CG
Answered by Chris G. • Biology tutor
5418 Views

Explain what is meant by a semi-fixed exchange rate? With reference to the BBC news story in the link below, explain why the Nigerian central bank increased interest rates and devalued their currency (the naira)?

http://www.bbc.co.uk/news/business-30196496 An exchange rate is the price of one currency in terms of another. When this rate is semi-fixed the exchange rate is allowed to fluctuate between a specified range...
OC
Answered by Owen C. • Economics tutor
15931 Views

How do you find the cube root of z = 1 + i?

Firstly we express z in polar form: z = R e i θ where |z| = (Re 2 + Im 2 ) 0.5 = (1 2 + 1 2 ) 0.5 = 2 0.5 θ = arg z = tan -1 (Im/Re) = tan -1 (1/1) = π/4 Therefore z = (2 0.5 ) e i π/4 We can add on any mult...
AE
19694 Views

How do you calculate the Earth's escape velocity?

The escape velocity is the speed that an object must have in order to have enough energy to escape the Earth's gravitational field. To calculate the escape velocity, we can apply the principle of Conservatio...
AE
Answered by Aldwyn E. • Physics tutor
26765 Views