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[Zapages]

Hey guys

Sorry for the trouble everyone... I'm having trouble with 3 Physics and 2 of which I'm not too sure of. I was wondering if anyone here would be kind enough to help. I would really appreciate it. Thank you.

Question 1: 

An RL series circuit has: 5.0-mH coil, 1.0-W resistor, 12-V battery, ammeter and switch. After the switch is closed for a long time, find the final value of the current.
a. 0.015 A
b. 1.5 A
c. 2.5 A
d. 12 A
e. 2 400 A 

Question 2: 
A 0.200-m wire is moved parallel to a 0.500-T magnetic field at a speed of 1.50 m/s. What emf is induced across the ends of the wire?
a. 0.150 V
b. zero
c. 0.600 V
d. 2.25 V
e. 1.00 V

Question 3:
A proton and a deuteron are moving with equal velocities perpendicular to a uniform magnetic field. A deuteron has the same charge as the proton but has twice its mass. The ratio of the acceleration of the proton to that of the deuteron is:
a. 1.
b. 4.
c. 2.
d. There is no acceleration in this case.
e. 0.5.


Not too sure of the following:
Question 4:
Which of the following locations has the smallest (in magnitude) magnetic declination?
a. western Colorado
b. the South Carolina - Georgia border
c. Washington state
d. Minnesota state
e. the San Francisco - Oakland area

I put B: The South Carolina and Georgia Border as the angle formed there is 0 degrees... or would it be Washington state with magnetic declination angle of 25 degrees... Not too sure....


Question 5:
A bar magnet is falling through a loop of wire with constant velocity. The south pole enters first. As the magnet leaves the wire, the induced current (as viewed from above):
a. is zero.
b. More information is needed.
c. is clockwise.
d. is counterclockwise.
e. is along the length of the magnet.

I put D, Counterclockwise... I remember from lecture that if put the bar magnet from North side then it will spin clockwise*I think*....

If someone is able to help me out, then that would be great. Thank you. I would really appreciate it.

-Zapages

 

[Zapages]

I was looking over Question 3 over... I think the answer is 0.5 as you have, but something in me is telling it is probably c. 2, because proton has 1/2 less mass than Deuteron.

Proton = P
Deuteron = 2P

As they are going on the same velocity....


I'm usually terrible at these type of problems.. Don't know why... I just 7 others before this... So I'm kind of out of it.

 

[emomoonbase]

Where the school system fails neogaf is there!

 

[Zapages]

anyone please help....

 

[Zapages]

Anyone please help... Sorry for the bump... I'm still having trouble with question 2...

 

[djkimothy]

I always hated physics.

I could only guess at question 3. The accelration should be 0.5 that of the proton?

f=ma, therefore acceleration is inversely proportional to the mass.

I don't know. I hate physics. Or let me rephrase, I hated magnetism topics in physics class. Right hand rule what?

 

[Escape Goat]

wtf is a deutron?

 

[Zapages]

I always hated physics.

I could only guess at question 3. The accelration should be 0.5 that of the proton?

f=ma, therefore acceleration is inversely proportional to the mass.

I don't know. I hate physics. Or let me rephrase, I hated magnetism topics in physics class. Right hand rule what?

That's what I thought for question 3... But one of my friends is saying its 2 as P = 2P, I'll try to talk to him.... I get confused as to what they are trying to ask, Proton to Deuteron or Deuteron to Proton... I mean I hate Magnetism and I'm a Bio major not Physics major in the first place.

The right hand rule is like what the hell rule for me sometimes as well.

 

[Jade Knight 08]

Question 1,2,3,5 got cut off at the side of the page when you scanned it. You need to give us the full questions before we can answer.



I'm really surprised that some of you can answer the questions even though it's cut off at the sides.

 

[Powerslave]

^slide the bar to the right. Tada.

 

[Bendelvio]

Question 1: Remember that a long time after the switch closes, the current will be constant. This means that there will be no voltage drop across the inductor. Therefore, by Kirchoff's Law, the voltage drop across the resistor must equal the voltage of the battery. Voltage drop across the resistor is V=IR, so solve for current.

Question 2: You want to focus on the directions of the velocity and the magnetic field. The moving wire is essentially a bunch of moving charges, so the force on each charge is F = qvB*sin(theta), where theta is the angle between the velocity vector and the magnetic field vector. Figure out theta and then you should be able to figure out the answer.

Question 3: Again we want to use F=qvB (theta = 90, so sin(theta)=1). We also know that F=ma, so ma=qvB or a=qvB/m. Now just sub in your relation for masses and take the ratio of the two accelerations.