I am doing coursework on ohms' law and need help
2007-03-03 04:35:13 · 12 answers · asked by Anonymous in Science & Mathematics ➔ Physics
A little less - heat increases th available energy,
2007-03-03 04:40:23 · answer #1 · answered by Anonymous · 0⤊ 0⤋
Greater. The heat excites electrons and impurities in the wire which collide with one another, thereby increasing the resistance of the wire.
You can do an easy experiment by placing a small copper coil of wire into a flask of water, and then heating the water, and measuring the resistance of the wire with an ohm meter as the water heats up.
2007-03-03 04:44:15 · answer #2 · answered by fenx 5 · 0⤊ 0⤋
For a uniform wire obeying Ohm's law, resistance INCREASES with heat - the reasons listed above are sufficient.
Note: when you perform an experiment in class along these lines, your results will never translate to a theoretically-correct-curve as predicted by all the pretty equations!
Experimental science is a lot messier (and therefore more enjoyable).
2007-03-03 07:48:12 · answer #3 · answered by Anonymous · 0⤊ 0⤋
The resistance of a metal wire increases with temperature.
See the link below.
2007-03-03 04:42:27 · answer #4 · answered by davidbgreensmith 4 · 0⤊ 0⤋
I think the heat makes the resistance greater because of the friction.
2007-03-03 04:42:42 · answer #5 · answered by Anonymous · 0⤊ 0⤋
Rt=Ro(1+@t) where Ro is the temp at 0degr Cent. @= 1/273 (approx) and Rt the resistence at t degrees cent.
So the resistence of the wire increases with temperature
2007-03-03 04:42:43 · answer #6 · answered by santmann2002 7 · 0⤊ 0⤋
it increases resistance of wire.this is so as the frequency of collisions between the lattice ions of wire and conducting elctrons increases due to thermal agitation.therefore resistance increases for wire that obeys ohm's law
2007-03-03 04:44:27 · answer #7 · answered by llcold 2 · 0⤊ 0⤋
heating increases the kinetic energy for the atoms in the wire ,
this means more collision btw the atoms and the electrons that are trying to get through , so it is harder for the electrons to get through , in result the resistance increases
does it help ?
2007-03-03 04:40:37 · answer #8 · answered by livefast_dieyoung 2 · 0⤊ 0⤋
Depends on what it is made of.
Generally resistance increases with temperature with most metals.
Carbon is the exception. Also semi conductors decrease in resistance.
2007-03-03 09:29:38 · answer #9 · answered by mad_jim 3 · 0⤊ 0⤋
when you get nervous, you are hot.
therefore, be calm.
the heat of the wire make resistance greater.
2007-03-03 04:41:18 · answer #10 · answered by Anonymous · 0⤊ 0⤋