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Hi I really need help!!!!!!!!

I need to do a presentation on Magnetism. The presentation needs to be enjoyable and informative. Basically I am sposed to teach them but I dunno wat to do. Any ideas?

Emma

Answers

The most common fault that students tend to make is to try to cover too much, to put together a powerpoint drenched in text and then read from a script. Perhaps you could research using the internet (or even books) until you spot something (to do with magnetism) that interests you. Take it as your aim to tell your (presumably) classmates about it. If you use powerpoint then only use pictures with hardly any text. Use the pictures to remind yourself what you wanted to say. The words will come. Keep your presentation to a few minutes only.

ianmoth

05 February 2013

Can you check my answers regarding ground energy states

Calculate the ground state energy of the B4+ ion (i.e. for n = 1), and the energy of the next four highest energy levels (i.e. for n = 2, 3, 4, 5).

My answers are:- boron z=5

n=1 E1 = -340 eV n=2 E2 = -85 eV n=3 E3 = -37.78 eV n=4 E4 = -21.25 eV n=5 E5 = -13.6 eV

Are these right? thanks for your help.

Emma

Homework help?

Carol eats a regular hamburger and drinks a glass of cow's milk for breakfast. Suppose that energy content of the hamburger and the milk are 2115 kJ and 565kJ respectively. What % of energy from the food does Carol use to push a sack of rice along a horizontal distance of 4.75 m? Her hands exerted a force of 50N applied 20° down with the horizontal.

Emma