PHYS UNIT 3

how to do this

Lets say I have magnetic Field of 5 Tesla

What electric field should I chose to only select particles traveling 10 m/s?

E=VB formula

What will happen to particles traveling slower vs faster for electric and magnetic fields

Electric Force will overpower Magnetic Force and particle will be forced downward VS Magnetic Force will overpower Electric Force and particle will be pushed upward

A charged particle is released from rest in a region with a constant Electric Field

or a constant Magnetic Field. what happens to each

The particle will accelerate in a straight line parallel to the electric field lines. BUT The particle will remain completely stationary and experience no force at all for constant mag field

1/2mv²=eV is the same as

KE=PE

The voice coil of a speaker has a diameter of 0.0025 m, contains 55 turns of

wire, and is placed in a 0.10-T magnetic field.  The current in the voice coil is

2.0 A.  (a)  Determine the magnetic force that acts on the coil and the

cone.  (b)  The voice coil and cone have a combined mass of 0.0200 kg.  Find

their acceleration.

A long straight wire carries a current of 8.0 A and a circular loop of wire carries a current of 2.0 A and has a radius of 0.030 m. Find the magnitude and direction of the magnetic field at the center of the loop

A proton travels through the center of a solenoid Does it feel a magnetic force? If so, what direction?

why is the last clockwise

turn ur hand around to look at it from the right from the view of the solenoid

when mag flux is incr vs decr

the direction of existing mag field and induced mag field is the opposite vs same

Which direction and how fast should you throw an electron at the equator so that the magnetic l force is equal and opposite to the gravitational force? Is this fast or slow

how to do this

why does this subtract

bc the left wire on the right is into the page and the right wire on the left is out of the page

HMW 7 Q6

r=mv/qB. then divide that by qe constant. it should be an integer because Electric charge is quantized, meaning that any net charge on an ion or atom must consist of an integer multiple of the fundamental unit of charge (the charge of a single electron or proton). Ions are formed by gaining or losing WHOLE numbers of electrons, so the total charge will always be a whole-number multiple of the elementary charge.

HMW 7 Q7. What Hall voltage (in mV) is produced by a 0.190 T field applied across a 2.60 cm diameter aorta when blood velocity is 55.0 cm/s?

V=BDV. so 2.7

How to determine pos vs neg charge from circular motion

counterclockwise is pos and clockwise is neg

HMW 8 Q2. If a current of 6.50 A is used, what is the force per tesla (in N/T) on the 20.0 cm wide loop? Also answer other two questions

use the regular right hand rule and then the F=ILB formula. F/B=IL

HMW 8 Q3. A current-carrying wire passes through a region of space that has a uniform magnetic field of 0.80 T. If the wire has a length of 2.8 m and a mass of 0.59 kg, determine the minimum current needed to levitate the wire.

Fg=Fb so mg=ILB. I=mg/LB.

HMW 8 Q4

For a circular loop, I think you curl your fingers in the direction of the current flowing around the circle, and your thumb points straight through the center to show the magnetic field passing through the loop. So, the direction of the field is out of the page for the circular loop. For a straight wire, you point your right thumb in the direction of the current, and you curl your fingers around the wire to show the magnetic field lines looping around it. So, from left to right the magnetic field is out of the page above the wire and into the page under it. From right to left, the magnetic field is into the page above the wire and out of the page under it. The direction of the I2 current is going from right to left then because the question says to choose the one where it is the opposite direction at the center of the loop. The opposite direction of out of the page from the circular loop in the center is into the page at the center above the wire so it is right to left.

For the second question, it is 9.74A. The circular loop formula is B=u0I/2R but for straight wire it is u0I/2piR formula and so you set them equal because they are connected like u0I/2R=u0I/2piR and get I1=I2/pi so I2=I1 times pi.

F=ILBsintheta is used to calculate the magnetic force experienced by a current-carrying straight wire when it is placed inside an external magnetic field. F=ILB formula calculates the actual physical push or pull force acting on a wire due to an existing magnetic field.

HMW 8 Q5. If a single circular loop of wire carries a current of 75 A and produces a magnetic field at its center with a magnitude of 2.40 x 10^-4 T, determine the radius of the loop.

B=uI/2R formula

HMW 8 Q6. how to do this

it is a diff formula which is F/L=u0I1I2/2piR which simplifies to F/L=u0I²/2piR because it is two parallel wires but the algebra is also different.

For current to flow from a live battery to a stalled car's battery, it has to travel outward through one cable (the positive clamp side) to deliver power, and then complete the loop by returning through the second cable (the negative/ground clamp side). Because electricity flows out through one wire and back through the other, the current in the two parallel wires is moving in opposite directions.

HMW 8 Q7. the wire carrying 500 A to the motor of a commuter train feels an attractive force of 3.60 ✕ 10⁻³ N/m due to a parallel wire carrying 5.00 A to a headlight. How far apart are the wires

F/L=u0I1I2/2piR. if the problem says same direction it is attractive but opposite direction is repulsive

HMW 8 Q8

do two F/L=u0I1I2/2piR formulas but subtract the two results and the direction is down. For the top wire, the straight wire current flows to the right while the top wire current flows to the left. Because these currents flow in opposite directions, they repel each other, which pushes the top wire downward away from the straight wire. For the bottom wire, the straight wire current flows to the right and the bottom wire current also flows to the right. Because these currents flow in the same direction, they attract each other, which pulls the bottom wire upward toward the straight wire. For the net direction, the top wire is closer to the straight wire at a distance of 9.50 cm than the bottom wire, so its downward repulsive force is much stronger. Since the stronger downward push wins out over the weaker upward pull, the overall net force on the loop is directed downward.

HMW 9 Q1

*clockwise is in ccw is out

HMW 9 Q2

HMW 9 Q3.

(a) What is the direction of the magnetic field due to the magnet in the center of the coil?

(b) As the magnet is moved in the direction indicated, how will the magnetic flux in the coil change?

(c) What is the direction of the induced magnetic flux in the coil?

(d) What is the direction of the induced current in the coil when viewed from above the coil?

HMW 9 Q4.

(a) Initially the switch is open. What is the direction of the induced current in Coil 2?

(b) Now the switch is closed. Immediately after the switch is closed, what is the direction of the induced current in Coil 2?

(c) A long time after the switch is closed, what is the direction of the induced current in Coil 2?

(d) Now the switch is opened once again. Immediately after the switch is open what is the direction of the induced current in Coil 2?

coil 1 is clockwise bc the short bar is the neg terminal and the long one is the pos terminal and charge alw goes from the pos (big bar) to neg terminal (small bar) ALONG the wire

HMW 9 Q5.

first is Vs/Vp=Ns/Np where s is secondary voltage/turns and p is primary voltage/turns so 2. the second is Is/Ip=Np/Ns and it is 64.6 YOU CAN FLIP BOTH FORMULAS LIKE DO VP/VS=NP/NS AND IP/IS=NS/NP SAME LETTERS FOR VOLTAGE OPPOSITE FOR CURRENT. for the third it is P=IV so multiply 2 by 4 for Vs x Is or .065 × 124 for Vp x Ip so 8.