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How can there be both molecular and non-molecular solids?

Non-molecular solids are of the type of metallic and ionic solids. They are held together by the strong electrostatic interactions of polar particles like ions and electrons. For example in metals the str...

Answered by Gregory P. • Chemistry tutor

6445 Views

How do you work out the work out the current through resistors in parallel?

[I would use the whiteboard to draw diagrams as I was talking]
A good analogy for circuits is that of water pipes. The wires are nice wide pipes with no resistance to flow. Resistors are sections of ...

Answered by • Physics tutor

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A cannon at ground level is firing at a fort 200m away with 20m high walls. It aims at an angle 30 degrees above the horizontal and fires cannonballs at 50m/s. Assuming no air resistance, will the cannonballs fall short, hit the walls or enter the fort?

solving horizontally, use v=s/t, where s=200, v=25(3)^1/2. Hence t=s/v=8/(3)^1/2 (where t is the time when the ball would reach the fort if it does not reach the ground)Solivng vertica...

Answered by • Maths tutor

3143 Views

List and briefly explain the two main mechanisms by which mammalian genes can be exchanged or 'translocated' between chromosomes. What are the importance of these types of recombination? (8 marks)

i. Homologous Recombination. A conservative, error-free DNA replication pathway that mainly allows for the repair of DNA under duress and also for the resetting of replication forks. The pathway is regula...

Answered by Benjamin A. • Biology tutor

2334 Views

Describe how allopatric speciation occurs.

In a population of a species a barrier forms (for example the formation of a new river, or the division between two islands). This leads to two isolated groups of the original species. In the two isolated...

Answered by Amelia P. • Biology tutor

2644 Views