What is the approximate efficiency of an electric motor whose power output is ½ hp and draws a current of 4,000 mA at 120 V?

Q: How long can a 12-V car battery supply 250 A to a starter motor if the battery has 4 x 10° J of…

A: Given values are - Vt=12VoltIt=250AChemical EnergyE=4×106J

Q: How much energy in kw-hrs is required to operate an 80% efficient, 5 horse power motor used 1 hour…

A: The total energy used is the sum powers used by motor in 30 days and by lamp in 30 days. The motor…

Q: A 1.4 kW electric heater is operating with 230 V and it is running for 2.5 hours. Calculate the…

A: The solution can be achieved as follows.

Q: A refrigerator requires 220 V ac to operate properly and during this time, it draws a current of 2.5…

A: From Ohm’s law, it can be concluded that if V is the voltage across any appliance and I is the…

Q: A battery of e.m.f. 12 V supplies a current of 5. for 2 minutes. How much energy is supplied in thị…

A: Given, Battery of emf, ε = 12 V Supplies current, I = 5 A Time, t = 2 min = 120 sec

Q: A battery may be rated in ampere-hours (Ah). A lead-acid battery is rated at 160 Ah. (a) What is the…

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Q: The power dissipated by an electric bulb is 40 W and the current flowing through the electric bulb…

A: Given, Power dissipation, P = 40 W Current flowing, I = 1.6 A

Q: Q.1/ Choos a, b, c, or d: 1- Which of the following factors would decrease the resistance of the…

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Q: A 1.9 kW electric heater is operating with 235 V and it is running for 2 hours. Calculate the…

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Q: An electric saw operates at a potential difference of 120 V and draws a current of 9.5 A. If it…

A: Total energy required is 45.6 kJ  Detail solution is in the image

Q: A 1-kW electric heater takes 15 min to boil a quantity of water. If this is done once a day and…

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Q: 2. What is the total cost of consuming 150KW at a 9e per kilo-watthour when a washing machine is…

A: Total cost =cost per kwh×energy in kwh. Power input=power outputefficiency. 1Hp=746 watts.…

Q: A fully-charged power bank with a full capacity of 100,000 mAH is used to supply a DC lamp of 12…

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Q: How much energy (in kilowatt-hours) is required to light a 100watt bulb (continuously for 1 year =…

A: Energy required to bulb= power* time in hours in a year. number of hours in a year = Number of days…

Q: An automobile battery supplies a current of 10A to the starter. It has a resistance of 1.25 Q. What…

A: Answer: 12.5V Explanation   a. It is not a valid option. The value of current should be 100A to…

Q: 3. A 2.8-kW electric heater takes 20 min to boil a quantity of water. If this is done once a day and…

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Q: The power to a device is 40 joules per second (J/s).  How long will it take to deliver 640J?

A: Given data: To power the device power required is P= 40 Joules/sec The energy required to be…

Q: 4. An ordinary light bulb is marked “60 W, 220V “. a. What is the resistance of the bulb? b. What is…

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Q: 8.An electric kettle is required to heat 0.6 kg of water from 10°C to boiling point in 5 minutes,…

A: In this question we will find resistance of heating element for electric kettle.....

Q: how many electrons pass a fixed point in a 120 Wat

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Q: What is the cost of operating for 24 hours a lamp requiring 1 amp on a 100-V line if the cost of…

A: In the question,  Find the total cost  If cost per KW-H= P10. 00 We know energy E= VIt

Q: A water jet consumes "3X50" W for 126 hours a week. What is the energy consumed (kWh) for a one-year…

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Q: The resistance of a wire varies directly with its length and inversely with the square of its…

A: Given a wire of same material, Case (1), Resistance of wire, R1=80 Ω Length of wire, L1=100 ft…

Q: Find the electrical current in amperes and electrical power in watts VOLTAGE: 231V -take note of a…

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Q: A voltmeter is accurate 97% of its full scale reading. i. If the voltmeter reads 210 V on 240 V…

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Q: A light bulb is rated at 30 W when operated at 120 V. How much charge enters (and leaves

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Q: What is the efficiency of a system if the output power is 9 hp and the input voltage is 240 V and…

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Q: 1. A current of 3A flows for 60 seconds through a lamp. How much charge has moved? 2. If 28000 C of…

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Q: constant current of 2 A is required to charge a car battery for 3 hours. The terminal voltage is 12…

A: Please refer the attached images for the complete answer..

Q: the sylvania supper saver 75 W light uses 20 watts, produces 1280 lumens, and costs $4.49. As an…

A: The efficiency is defined as the ratio of the output to the input. For a light bulb output is the…

Q: What is the resistance (Ohm) of a soldering iron that draws 0.8333 A at 120 V? A toaster with 8.27…

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Q: A battery of e.m.f. 15 V supplies a current of 2 A for 5 min. How much energy is supplied in this…

A: In this question we will find energy supplied by battery...

Q: 8. A light bulb, having a tungsten-filament, draws 2.85 A at 220 V when running at normal condition.…

A: Resistance at any temperature =( resistance at 17 degrees )×(1+(temperature coefficient of…

Q: If a DC generator delivers 180W to a load, what is the minimum mechanical power (in watts) needed to…

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Q: A  standard 12 V car battery has an ampere-hour rating of 40 Ah, Whereas a heavy-duty battery has a…

A: Ah rating of given batteries are B1=40Ah B2=60Ah And Voltage=12V Although Ah rating of a battery…

Q: What is the cost of using a 5Hp motor for two hours if the rate is P50.00 per kWhr

A: Given, Rating of motor is 5 HP  The motor in operation for 2 hours. Rate of operation is P50.00…

Q: 8.12 A 340 Ah battery supplies a constant current load of 17 A for 8 h each day. Compute the…

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Q: A 1.8 kW electric heater has a resistance of 18 Q and it is running for 2.5 hours. Calculate the…

A: Power of heater P=1.8kW Resistance R=18ohm Running time 2.5Hours Find the energy and current?

Q: 5. A DC Electric motor consumes 36 MJ when connected to a 250 V supply for 1 hour. Fid the power…

A: Ans. Is shown below

Q: HW 1: How much current, i, is drawn by an electrical device with resistance 15 N at 110 V?

A: Dear student as per our guidelines we are supposed to solve only one question.kindly repost other…

Q: An electric motor develops a mechanical power of 20hp with 88% efficiency. Find its electric input…

A: The major classification of DC motor are: Series motor Shunt motor Compound motor In shunt motor…

Q: Calculate the energy cost of an electroplating process running at 0.61 V and 30.7 A for 3863 s…

A: In this question, Calculate the energy cost of an electroplating process running at 0.61 V and 30.7…

Q: A water jet cinsume 3450 W for 126 hours a week.  1. What is the energy consumed (kWh) for one-year…

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Q: 5. How much electrical energy is transferred to thermal energy in 2.50 hrs by an electrical…

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Q: An electric cooker is powered by a 12V battery. The battery supplies a current of 4.5A for 30…

A: 1.  If I represent the current flowing through a circuit for a duration T, then the charge (q) which…

Q: 6.1 A Car battery is rated for 12 Volts, 5 Ah rechargeable battery can be operated for about 10…

A: Given, A battery with V=12 VQ=5 Aht=10 h

Q: How much matter will be converted entirely to energy to produce 25 million kWh?

A:

Power Measurement

According to Blondel's theorem, the total power is measured with one less number of wattmeters than the number of wires present in the system. So, a single-phase and two-wire system will require one wattmeter and a single-phase and the three-wire system will require two wattmeters, and a three-phase and the three-wire system will also require two wattmeters and a three-phase and the four-wire system will require three wattmeter devices. The wattmeter is a device that measures power using one voltage and one current input as shown in the above figure. Multiple current or voltage input pair cables are used by many power analyzers and digital storage oscilloscopes (DSOs) for measuring watts, in effect within a single instrument acting as multiple wattmeters. It is possible to measure three-phase and four-wire power with one correctly specified power analyzer.