How much heat does one degree of electricity produce

How much heat does one degree of electricity produce

The theoretical value is 3600 kJ (860 kcal);
The conversion efficiency of electric energy into heat energy is different in different ways
About 80% resistance conversion: 1 kwh = 3600 x 0.8 = 2880 kJ (688 kcal)
About 90% induction conversion: 1 kwh = 3600 x 0.9 = 3240 kJ (774 kcal)
How much heat can one degree of electricity produce in one minute?
Under the ideal condition, if the loss is completely ignored, the heat of 3600000 joules can be generated by the heating tube for one degree of electric energy. One degree of electric energy is also called one kilowatt per hour, which can be completely converted into heat of 1000 × 3600 = 3600000 joules. Similarly, 3600000 joules of energy can be converted into one degree of electric energy
How many calories is 1000 joules
1 calorie = 4.18 joules
1000 / 4.18 = 239.3 calories
What do Li Shizhen, Zu Chongzhi, Hua Tuo, Zhang Heng and Bi Sheng do?
Li Shizhen was an outstanding pharmacist in Ming Dynasty, who wrote the great work compendium of Materia Medica
Zu Chongzhi (429-500 A.D.) is an outstanding mathematician and scientist in China. He was born in the northern and Southern Dynasties, Han nationality, and the word Wenyuan. He was born in the sixth year of Yuanjia, Emperor Wen of Song Dynasty, and died in the second year of Yongyuan, Marquis of Qi Hun. His ancestral home is Qiu county, Fanyang county (now Laishui County, Hebei Province). In order to avoid war, Zu Chang's grandfather moved from Hebei to Jiangnan, He was in charge of civil engineering, and his father was also an official in the imperial court. He received scientific knowledge from his family as a child, and entered Hualin Province as a young man, He was engaged in academic activities. In his whole life, he successively served as an official in southern Xuzhou (today's Zhenjiang City), engaged in history, government enlistment, Lou county (today's northeast Kunshan City) order, yezhe pushe, Changshui Xiaowei and so on. His main contributions include mathematics, astronomy, calendar and machinery
Hua Tuo was famous in medicine, especially in surgery. Later he was killed by Cao Cao
Bisheng was a common man in the Northern Song Dynasty. He invented clay movable type printing in the middle of the 11th century
Current voltage resistance formula
R = u / I Ohm's law
I want to calculate the resistance of the wire. How to calculate it through the length? The length is 100m, copper wire, 2 * 1.2mm cubic
Let's use the resistivity formula to calculate. The formula is: r = ρ (L / a), where r -- the resistance of the conductor, in ohm, ρ -- the resistivity of the conductor, in ohm · cm (check in the electrician's manual, different materials have different resistivities), l -- the length of the conductor, in cm, a -- the cross-sectional area of the conductor, in square cm. The resistivity of copper is 0.0172 ohm · cm
The 10 meter long copper conductor with 10 ohm resistance is divided into two equal parts to form a 5 meter long copper conductor. The resistance of the combined copper conductor is 2.5 ohm
After separation, the resistance of each section is half of the original, that is, 5 Ω
According to the relationship between total resistance and branch resistance of parallel circuit, 1 / rtotal = 1 / R1 + 1 / R2
It can be seen from the data that r = 2.5 Ω
What are the inventions / contributions of Sima Qian, Confucius, Cai Lun, Edison, Newton, Watt and Zu Chongzhi?
It's not good upstairs
Sima Qian wrote historical records
The Analects of Confucius' later works
Cai Lun paper
There are too many Edisons, light bulbs, movies, phonographs and so on
Newton had the first, second and third law of gravity
Watt invented steam engine
Zu Chongzhi deduced the PI
Voltage calculation formula of series circuit
The total voltage is u, the total current is I, and the total resistance is r,
There are two electrical appliances, its current I1, I2, resistance R1, R2, voltage U1, U2
I = I1+I2
U =U1 +U2
The resistance in a series circuit is equal to the sum of the resistance of each consumer
U1=R1*U /R1+R2
U2=R2*U /R1+R2
I = I1 + I2 this is not true. Each current in the series circuit is equal
U1 = R1 * U / R1 + R2, you forgot to add brackets
U / (R1 + R2) is I1, then U1 = R1 * I1. See?
U1 = R1 * U / R1 + R2 is the voltage at both ends of R1. Because they are connected in series, the current is equal
I = u / r = u / (R1 + R2) voltage equals IR1 = R1 * U / (R1 + R2)
U2, you understand!
What is the resistance of 50 square 100m copper wire?
The resistivity of copper P = 1.55 * 10 ^ - 8 * (1 + 4.33 * 10 ^ - 3 * t) (Ω m)
When t = 200, P = 1.55 * 10 ^ - 8 * (1 + 4.33 * 10 ^ - 3 * 200) = 2.89 * 10 ^ - 8 (Ω m)
The resistance of copper wire with sectional area of 1 square millimeter at 200 ℃ and 30 cm is r = PL / S = 2.89 * 10 ^ - 8 * 0.3 / 10 ^ - 6 = 8.68 * 10 ^ - 3 (Ω)
When t = 500, P = 1.55 * 10 ^ - 8 * (1 + 4.33 * 10 ^ - 3 * 500) = 4.91 * 10 ^ - 8 (Ω m)
The resistance of copper wire with sectional area of 1 square millimeter at 200 ℃ and 30 cm is r = PL / S = 4.91 * 10 ^ - 8 * 0.3 / 10 ^ - 6 = 1.47 * 10 ^ - 2 (Ω)
You first set my best answer, I Baidu HII teach you
You go and test it. Because now the quality of copper coin is good or bad, it can't be simply calculated by formula