Science & Mathematics - 1 February 2007

Question: a plate carries a charge of -3.0 uC, while a rod carries a charge of +2.0 uC. How many electrons must be transferred from the plate to the rod, so that both objects have the same charge?

My Approach:

N= q/e = -2.0e-6/-1.6e-19 = 1.25e13 electrons transferred

something doesn't seem right about this problem. the prof didnt mark this wrong, but he marked -2.0e-6 C wrong? anyone with the fix?

2007-02-01 00:33:10 · 2 answers · asked by Anonymous in Physics

Tell me the best ideas to make a model of earth and the actions like earthquake and volcanic eruption scientifically with low cost as possible.

2007-02-01 00:28:05 · 9 answers · asked by GOKUL S 1 in Astronomy & Space

A torch on the end of a piece of string, in the centre of a cylinder, is spinning round at the speed of light. At what speed is the light from the torch hitting the inside wall of the cylinder, if light can not go faster than186,000mp/second. Surely, it would be travelling faster than this, if the point at which the torch was spinning was already travelling at the speed of light?

2007-02-01 00:27:37 · 7 answers · asked by Anonymous in Physics

I am trying to react ethanol and ethanoic acid together to form Ethyl Ethanoate, i am trying to increase the yield so is it best to have more ethanol to shift the equilbrium to the products side? I am use reflux but which is the best catalyst for this, i have read sulphuric acid quite a few times, if that is the best what makes it better than e.g. hcl?

2007-02-01 00:26:52 · 5 answers · asked by jewellui 2 in Chemistry

2007-02-01 00:25:34 · 1 answers · asked by Anonymous in Engineering

An object moves uniformly around a circular path of radius 21.5 cm, making one complete revolution every 2.20 s.
(a) What is the translational speed of the object
(b) What is the frequency of motion in hertz?
(c) What is the angular speed of the object?

2007-02-01 00:25:01 · 3 answers · asked by Kelly C 1 in Physics

2007-02-01 00:24:22 · 6 answers · asked by enescu i 1 in Astronomy & Space

The motion of an object is described by the equation below.
x = (0.20 m) cos(t/6)

(a) Find the position of the object at t = 0 and at t = 0.40 s. t = 0 m
t = 0.40 s 0.99
Your answer differs from the correct answer by 10% to 100%. m
(b) Find the amplitude of the motion.
m
(c) Find the frequency of the motion.
Hz
(d) Find the period of the motion.
s

2007-02-01 00:22:56 · 2 answers · asked by Kelly C 1 in Physics

2007-02-01 00:21:08 · 2 answers · asked by kumar 1 in Engineering

For joining a competition I want a best idea of making working models. It should be subjected to science.Are you a scientist? Please help me!

2007-02-01 00:19:53 · 1 answers · asked by GOKUL S 1 in Engineering

Can u suggest me any website or link where i can get details related to the topic Polynomials...bt not for 9th standard. For 10th standard i.e the level should b higher

2007-02-01 00:17:35 · 7 answers · asked by Anonymous in Geography

i need the answer for my botany exam paper.it is related to biotechnology.

2007-02-01 00:14:31 · 3 answers · asked by iolahardy 1 in Botany

the snow is don't even a inch!

2007-02-01 00:14:24 · 11 answers · asked by grantndee 1 in Weather

I KNOW IT WONT WORK BUT

What physically would happen to this persons body, how would the heart react to it?

2007-02-01 00:09:33 · 8 answers · asked by Anonymous in Biology

2007-02-01 00:09:14 · 3 answers · asked by deadman 2 in Mathematics

i think that two particles that are the same cannot be in the same time period or somethings going to happen.

2007-02-01 00:07:59 · 15 answers · asked by ♥lois c♥ ☺♥♥♥☺ 6 in Physics

2007-02-01 00:04:46 · 3 answers · asked by Anonymous in Chemistry

2007-02-01 00:03:49 · 6 answers · asked by Gen. Zyril Cydryk 1 in Physics