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1. A lamp consumes 1kW of electricity in 25 hours. What is the power of this lamp? 2. How many hours can a 220V 50W bulb work with 1000W of electricity 1. A lamp consumes 1kW in 25 hours. What is the electric power of this lamp? 2. How many hours can a 220V 50W bulb work with 1000W electric energy? (detailed solution process and formula are required) 3. How much energy is consumed by a 110 V, 100 W electric appliance working for one hour? If the power ratio of a and B dual-purpose electrical appliances is 4:1 and the power on time ratio is 2:1, what is the power consumption ratio?
A: 1. What is the electric power of a lamp that consumes 1kW in 25 hours? 1 kwh = 1000W. 25 hours, then the power is p = 1000 / 25 = 40W. 2. How many hours can a 220V 50W bulb work with 1000W? P = 50W, then t = 1000 / 50 = 20 hours. 3. P = 100W, 1H = 3600 seconds, then the power consumption is 1 hour
There are two light bulbs connected to 110 V power supply, one is 220 V 40 W, the other is 110 V 25 W, which is brighter
220 V 40 W resistance R1 = U1 & # 178 / P1 = (220 V) & # 178 / 40W = 1210 Ω 110 V 25 W resistance R2 = U2 & # 178 / P2 = (110 V) & # 178 / 25W = 484 Ω two bulbs are respectively connected to 110 V power supply, the voltage is equal, according to P = u & # 178 / R, P is inversely proportional to R, R1 > R2, so P1 '< P2'110 V 25 W bulb
It costs 24 yuan to buy 20 light bulbs (25 watts and 40 watts) in the school. Among them, each 40 Watt light bulb costs 1.4 yuan, and a total of 12 light bulbs are bought. How much is each 25 watt light bulb
Set a 25 watt bulb at x yuan per bulb
（20-12）x+1.4x12=24
x=0.775
775, which is the solution of the original equation
A: each 25 watt bulb costs 0.775 yuan
Right?
There are two kinds of bulbs, labeled (110 V 60 W) and (110 V 25 W), which are connected to the home lighting circuit
(1) Can you use one in series? Please explain the reason
(2) If two kinds of light bulbs are mixed in the same circuit and both of them can emit light normally, how many light bulbs should be used and how to connect them?
I want to ask the second question. The website says, "use 60 watt lamps in parallel, use 25 Watt lamps in parallel, and then use them in series. Only when each voltage is 110 V, can they light normally. Why can't we use two 60W lamps in series, and two 25W lamps in series, and then connect them in parallel, and then connect them into the circuit? In this way, the number of lamps only needs four, Why not?
(1) No, because the resistance is not the same, so in the circuit, one will get less than 110V, the other will get more than 110V
(2) Because in order to obtain 110V voltage for both groups of bulbs, the total resistance of the two groups of bulbs must be the same, so different numbers of bulbs should be connected in parallel and then connected in series
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- 2. There is an electric lamp, which consumes 100 watts when connected to the power supply. Connect it in series with another resistor and then connect it to the same power supply. The power consumed by the resistor is 9 watts. The strategy of bulb consumption at this time is proposed
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