2. Knowing that the ammeter must be connected in series with the circuit and the

Question

2. Knowing that the ammeter must be connected in series with the circuit and the voltmeter must be connected in parallel, what does this tells you about the internal resistance of each device? 3. Explain what effect the DMM might have on the circuit when inserted to measure the current. 4. Small household electrical devices, such as vacuum cleaners, televisions and floor lamps, each drawa different amount of current, but all require 120 volts to operate. Are the outlets in of a power-strip, then, wired in series or parallel? Why? 60 60 100 5. For the circuit to the right, what direction does the current flow? Give a qualitative explanation for your answer using the concepts from today's experiment. 300 300

Explanation / Answer

2)Our main aim in conducting the experiment is not to alter results at any cost.The only way in which current or voltage in the circuit remains unaltered is when the resistance do not changes appreciably in the circuit on the introduction of a new device.Now if ammeter is connected in series then it implies that it does not changes the resistance of the circuit appreciably....hence the resistance of ideal ammeter is zero and that of a real one is very less.In case of voltmeter the resistance is fairly too high and that's why it is connected in parallel so that it offers high resistance to the current flowing the voltmeter branch of the circuit...due to which all the current passes through the branch of the resistor across which voltage is to be measured.

3)) When a DMM is connected in a circuit then it increases the resistance by 2-3 ohms due to which the current which is to be measured decreases.Hence the value of current which we obtain from DMM is little less than the actual current flowing in the circuit.

4) Answer lies in the language of question itself.If every appliance need rge same amount of voltage then obviously it must be a parallel arrangements.All appliances must be connected in parallel because they all will require same voltage.If they are connected in a series circuit then voltage across each appliance will be different.Hence parallel arrangement.

5) Current always moves from a region of high potential to low potential.In this case the direction will be from the resistor on the 60 ohm side(near to positive end of voltage source) to the 60 ohm(near to the negative end of the voltage source).

However the current will not flow from 100 ohm branch because it's a weight stone bridge(ratio of the two resistors on the left of 100 ohm branch is equal to the ratio of the two resistors on the right of the 100 ohm branch)

Related Questions

Navigate

• Browse (All)
• Browse 2
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.