# Recent content by shanie

1. ### Power of the sun

Thank you! :)
2. ### Power of the sun

Homework Statement I'm carrying out a lab to investigate the power of the sun. I'm supposed to compare the light intensity of a 100W light bulb with the light intensity from the sun, by comparing the radiating heat on my cheeks (one cheek pointing to the sun, the other to the bulb). I found...
3. ### Magnetic force of a proton

Homework Statement A proton with the speed 3.7*10^6 m/s is moving in a magnetic field, parallel to the field. The magnetic B-force is 0.45T. a)Draw a figure that shows the proton in the magnetic field. Indicate the direction of the proton's velocity, the direction of the magnetic field and...
4. ### Magnetic field strength between two wires homework

Thanks so much for your help!
5. ### Magnetic field strength between two wires homework

For points to the left of the current going vertically upward, the field is anticlockwise according to the right hand rule. Vertically downward gives clockwise direction.. So for b) when the point is closer to the wire with current going anticlockwise, B will be going out of the paper (point)...
6. ### Magnetic field strength between two wires homework

Oh of course, it's 0.06m which gives B=25μT. For a) this would make 50μT (25+25) in the point (with B pointing in which direction? since each field goes its own direction after having left the middle..) b) it would make 12.5μT from the left (12cm away from the wire as specified), and 6.25...
7. ### Magnetic field strength between two wires homework

Thank you :-) I drew a picture like you said and I also drew the arrows of the magnetic field according to the right hand rule. Now I realised that the field arrows coming from each wire points in the same direction once they reach the area in the exact middle of the wire (the area where the...
8. ### Magnetic field strength between two wires homework

The numbers I used where the current I=7.5A and the radius from each wire r=0.12m and then the constant k=2*10^-7. Giving: B=kI/r => B = (7.5*2*10^-7)/0.12=1.25*10^-5 T..? Is this incorrect? The direction for the left wire (current going upwards) is anticlockwise, and for the right it is...
9. ### Magnetic field strength between two wires homework

But if the location of the point isn't specified, do I just assume that the two magnetic fields affect the point equally? That is, assuming that the point is in the exact middle of the two wires. That would essentially give me a magnetic field of 0 T for question a)? And in b), the correct...
10. ### Magnetic field strength between two wires homework

Homework Statement Two straight parallel wires are placed vertically on a wall. The distance between the wires is 12 cm and the current through each one is 7.5A. In the left wire the current is directed upwards and in the right one the current points downwards. Determine the magnetic field...
11. ### Coulomb's law

Oh, I see! Thanks :)
12. ### Coulomb's law

Oh, you mean for every action there is an equal and opposite reaction? So if q2 works on q1 by 55μN, this means that q1 works on q2 by 55μN? So then in b) I just add them together to make 110μN, which I then plug into coulomb's law: 110 μN = (k*q1*q2)/d^2 And solve for d?
13. ### Coulomb's law

Homework Statement Two small charges q1 = +2.65 nC and q2=-4.75nC are at a certain distance from each other. Q1 is affected by a force of 55μN from q2. a) how large is the force on q2? Draw a figure that shows the electric forces that work on q1 and q2. b) determine the distance between the...
14. ### Forces on a painting

Thank you, that really helped! I was just wondering, does the nail exert an upward normal force on the wire (seeing as another force must help keep the wire and painting in equilibrium)? And if so, then is it, in this case, equal to the gravitational force since it must be perpendicular to the...
15. ### Forces on a painting

I realize now you meant free body diagram, so what I figured out was the following: a) The forces on the nail is the gravitational force from the wire and the painting, pointing downwards. The nail works on the wire by a normal force that is as large as the gravitational force 5.9N but in the...