The resistance of iron is less than mercury and we know that resistance is inversely proportional to the current. Therefore, iron is better as a conductor of electricity when compared to the mercury. The correct option for the unit of electrical resistance is d) Ohm. B) When a 12V battery is connected across an unknown resistor, there is a current of 2.5mA in the circuit.
The greater the diameter of the cylinder, the more current it can carry . In fact, R is inversely proportional to the cylinder’s cross-sectional area A. The electrical resistance is the opposition of electrons when moving through a conductor. Or in other words, the difficulty found by a current when traversing a closed electrical circuit, which allows slow or reduce the free flow of electrons.
Two electric circuits I and II are shown in figure. The potential difference across each is the same. Two parallel beams of electromagnetic radiation with different wavelengths deliver the same power to equivalent surface areas normal to the beams. Show that the numbers of photons striking the surfaces per second for the two beams are in the same ratio as their wavelengths. The electric field is perpendicular to the surface.
Which of the following is not an example of a charge carrier. Indicate whether the following statements are true or false. Power is related mathematically to the amount of energy transfer by work by integrating over time. The thicker wire has one-fourth the resistance of the thinner wire. A has twice the resistance as B. A and B have same resistivity.
Change its resistivity, length, and area to see how they affect the wire’s resistance. The sizes of the symbols in the equation change retailing is defined as the set of business activities that along with the diagram of a wire. Three V-I graphs are drawn individually for two resistors and their series combination.
D) Draw a circuit diagram showing two electric lamps connected in parallel together with a cell and a switch that works both lamps. Mark an A enclosed in a circle on your diagram to show where an ammeter should be placed to measure the current. A) With the help of a circuit diagram, deduce the equivalent resistance of two resistances connected in series. The potential difference across each resistor is same as the resistors are connected in parallel and the voltage across these resistors are the same.
Some alloys have been developed specifically to have a small temperature dependence. Manganin , for example, has α close to zero , and so its resistivity varies only slightly with temperature. This is useful for making a temperature-independent resistance standard, for example. The size of the electric current in a electrical conductor is a function of which of the following?