- #1
Cocoleia
- 295
- 4
Homework Statement
Homework Equations
The Attempt at a Solution
I attempted all of the parts:
You have d wrong. The formula you quoted is not quite right.Cocoleia said:think I did the right things for a-b-c-d
Ah I see it should be 1/Req. If I change that, will the following steps be right assuming I use that value ?haruspex said:You have d wrong. The formula you quoted is not quite right.
Your method in e) is right.Cocoleia said:Ah I see it should be 1/Req. If I change that, will the following steps be right assuming I use that value ?
If you read posts 2 and 3, you'll see that d) was wrong, and this led to the wrong expression in e.kuruman said:(a)-(d) look correct.
(e) is incorrect. You need to take the ratio as the question indicates, not the product.
How do I calculate it without assuming this? By the way, this isn't homework, I am just working on problems to prepare for an exam tomorrow.haruspex said:Your method in e) is right.
In f, you seem to have assumed all of I is in the inner wire when calculating the current density there.
One way would be to suppose the potential applied to the wire is V and compute what current would flow in each component.Cocoleia said:How do I calculate it without assuming this? By the way, this isn't homework, I am just working on problems to prepare for an exam tomorrow.
Resistance is the measure of how difficult it is for electricity to flow through a material. It is represented by the letter R and measured in ohms (Ω).
The cross-sectional area of a wire refers to the size of the wire's cross-section. The larger the cross-sectional area, the lower the resistance will be, as there is more space for electrons to flow through the wire.
The longer the wire, the higher the resistance will be. This is because the electrons have to travel a longer distance, encountering more obstacles and increasing the overall resistance.
The type of coating on a wire can affect its resistance in different ways. Some coatings, such as copper, have low resistance, while others, such as rubber, have higher resistance. The thickness of the coating can also impact resistance, as a thicker coating will provide more obstacles for electrons to pass through.
You can calculate the resistance of a long coated wire by using the formula R = ρL/A, where R is resistance, ρ is the resistivity of the material, L is the length of the wire, and A is the cross-sectional area of the wire.