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In the figure below, six charged particles surround particle 7 at radial distances of either d = 1.0 cm or 2d, as drawn. The charges are q1 = +6e, q2 = +7e, q3 = +e, q4 = +4e, q5 = +4e, q6 = +2e, q7 = +8e, with e = 1.60 10-19 C. What is the magnitude of the net electrostatic force on particle 7?

http://www.webassign.net/hrw/21-43.gif

I don't know what i am doing wrong. All the dots in the negative regions, i labeled as -k. How do i do this problem correctly?

A 5.8 kg toy race car can move along an x axis. The figure below gives Fx of the force acting on the car, which begins at rest at time t = 0. (The vertical axis is marked in increments of 1 N.)

http://www.webassign.net/hrw8/9-p-030-alt.gif

What is the momentum of the car at t = 4.0 s?

In unit vector format please.

A 4.4 kg bundle starts up a 30° incline with 140 J of kinetic energy. How far will it slide up the plane if the coefficient of friction is 0.30? (in meters)

How much work is done by a force = (4x N) +(5 N), with x in meters, that moves a particle from a position i = (6 m) +(4 m), to a position f = -(2 m) -(2 m)?

I keep getting -54J but that is not the answer. Can someone explain how to do this problem? Thank you

I know how a regular TV works, but does a 3DTV work the same way, but with the use of stereoscopy for the inside? If you can, I would like a functional block diagram but it is not needed! Thanks!

I'm working on a lab and I don't know a pre-lab question. Can someone help me through this process??

Question: Suppose during the lab you read 71 degrees from the protractor. If the initial speed of the ball is 9.4 m/s the vertical component of the initial velocity of the ball is??

Thanks for any help!

Okay, so I know that voltage remains constant in a parallel circuit, but why does it? Can someone briefly explain this to me? Thanks!

SO my sophomore year of college starts in August of 2012. When should I apply for a loan for that year?

How can I switch back to the regular one?

Where can I find an electric motor in common children toys?

How do I know that hydrogen produces a red light from the n=3 level to the n=2?

Thank you for any help!

A man with a boat is located at point P on the shore of a circular lake of radius 8 miles. He wants to reach the point Q on the shore diametrically opposed to P as quickly as possible. He plans to paddle his boat at an angle t (0<t<pi/2) to PQ to some point R on the shore, then walk along the shore to his Q . If he can paddle 2.8 miles per hour and walk at 3 miles per hour, what is the shortest possible time it will take him to reach Q?

What are the intervals of positive and negative concavity and the inflection points of each?

1) (4e^x)/(4e^x +6)

2) (3x^(1/3))(x+21)^(2/3)

So I have a mac computer and I need a windows program to do homework with. Instead of always going to a library to do this homework, i looked up parallels. I think I might buy it. My question is, will my computer be more at a risk to get a virus?

Is it typical for students to get a loan their sophomore year in college? I don't come from a rich family so the first year we can pay by ourselves. Next year we will have to get a loan. Will it be typical for students and families to do so? By the time i graduate, i will be 63 grand in debt with loans.

What are the phases of each of these equations:

Sr(OH)2 + 2HNO3----> 2H2O+ Sr(NO3)2

and

Pb(NO3)2 + Na2SO4--> PbSO4+ 2NaNO3

A solution of 120mL of 0.170 KOH, is mixed with a solution of 280mL of 0.170 NiSO4

The balanced equation is 2KOH+NiSO4---> K2SO4+Ni(OH)2 and .946 of precipitate forms.

What are the concentrations of

Ni+2 ions,

SO4 2- ions,

and K+ ions

??

If you take a 13.5- portion of the stock solution and dilute it to a total volume of 0.500 , what will be the concentration of the final solution?

I have been wearing contacts for about 6 years. I recently ordered glasses for convenience. I'm used to clear vision but when I put the glasses on, I start to feel sick to my stomach- In a way, dizzy. Is this normal? Do i just have to get used to how glasses work?

I'm new with the whole credit card/debit card information. I just recently got a fifth third mastercard. I went to a gas station to pay for my gas with it. Would this amount be taken as a credit card, or does it just automatically take money out of my savings? Thanks for any help!