Recent content by xma123

Thanks very much for your patience, much appreciated

Oh damn, they're positive charges, so the field acts downwards away from the top charge. This would give a "negative" field in the y direction and so option 4 is correct?

Apologies, it's late. The j vector acts in the y direction, so the top charge would act in the upwards of y, +j vector and therefore option 3. By positive or negative I was referring to the difference betweent options 3 and 4.

The picture is all the info given on this

So due to each charge the field is E=kq/r2 The 4 in the middle cancel, giving a field of either positive or negative of the single field charge above. So would the answer be option 3?

http://imgur.com/a3vxU Really haven't a clue how to go about this, it's the last question on the paper and nothing before it is anything near as complex as this. Any help much appreciated

Two identical twins, Romulus and Remus, are the same age. Remus is abducted by space aliens and flown to a nearby star and back at almost the speed of light, while Romulus remained stationary. When the twins meet again, Romulus is significantly older. Briefly explain why we may not consider that...

Could anyone explain how Δs is related to the proper time interval?