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Single electrons travelling at 550 ms^-1 are passed through a diffraction grating with a spacing between the slits of 2.5 micrometers. What would the angle between the zeroth and first maximum of the resulting interference pattern be?

This is a question based loosely around the specification of the OCR A-Level Physics B course, requiring the student to recall two important quantum mechanical relations, first with one from the A2 part o...

Answered by Tom H. • Physics tutor

1866 Views

Solve the equation cosec^2(x) = 1 + 2cot(x), for -180° < x ≤ 180°.

First, we want to convert the equation to a simpler form involving just one function of x. Squared trigonometric functions are normally good candidates for simplification, thanks to the trigonometric iden...

Answered by Max H. • Maths tutor

10778 Views

Integrate cos(x)sin^2(x)

Answer: sin^3(x)/3 + c
The student can either solve by inspection by noticing that the derivative of sin^3(x)=3sin^2(x)cos(x).
OR
The student can use the longer method of integration by par...

Answered by Milan S. • Maths tutor

8210 Views

0.04 moles of sulfur trioxide is placed in a flask (1.50dm^3) and allowed to reach equilibrium at 600 degrees. If 30% of the sulfur trioxide decomposes to sulfur dioxide and oxygen - what is the equilibrium constant?

The easiest way to start your answer is by writing out the equation for the reaction {2SO₃ (g) <-> 2SO₂ (g) + O₂ (g) } and considering what the equilibrium constant ...

Answered by Isobel W. • Chemistry tutor

3307 Views

What caused the collapse of the Weimar Republic?

A useful way of tackling this question would be to split your ideas of the possible factors into those based on structural phenomena and those driven by the agency of individuals. In this way, your answer...

Answered by Sebastian B. • History tutor

2984 Views