Recent content by fysics4fun

mpkannan makes it clear- you must look at everything in context before deciding the signs on everything. A question like "what is the sign on work" is too vague. Two statements of the First Law of Thermo seen in textbooks: dU = Q + W and dU = Q - W W in the first statement is "work...

We are not provided any details other than the problem stated just as it is. I am a teacher, and I put this question on Friday's exam (as extra credit) without looking at it very closely, unfortunately (it looks easy at first glance!) Now I have to explain it tomorrow and I don't know how :P...

Homework Statement A very large open water tank has a 50 cm diameter output pipe connected 10 m above the water main which is 6 cm in diameter. If the gauge pressure in the water main reads 9.8 E4 Pa what is the speed at which the water is supplied? The answer should be 0.5 m/s but I can't...

I didn't think it was advanced either, until I couldn't get the right answer. ..I thought there was an "advanced" answer to what seemed like a simple question :P Sorry to waste your time. But I already knew which equation to use, so this doesn't help. Can someone please tell me the actual...

Homework Statement A very large open water tank has a 50 cm diameter output pipe connected 10 m above the water main which is 6 cm in diameter. If the gauge pressure in the water main reads 9.8 E4 Pa what is the speed at whic the water is supplied? Homework Equations Bernoulli's...