Answer:
cần cung cấp 70 độ vì nước sôi ở 100°C
Explanation:
Answer:
The cup with 0.5L
Explanation:
To know what amount of water you take into account the specific heat of the water. The specific heat of water is:

Thus, 4186 J of energy are needed to icrease the temperature of 1 kg water in 1°C. Then, more grams of water will need more energy.
You have that one cup has 0.5 L and the other one has 750mL = 0.75L
The second cup of water will need more heat because the amount of water contained in the second cup is greater than in the first cup with 0.5L
Answer:
a.73.3%
b.26.6%
Explanation:
a. The efficiency is the energy output, divided by the energy input, and expressed as a percentage.
#Given the energy input as 1500J and the subsequent output as 1100J, the TV's efficiency is calculated as:
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Hence, the TV has an efficiency of 33.3%
b. From a above, we know that the TV has an output of 1100J and input of 1500J.
-We therefore calculate it's wastage as the difference between output and input:
<em>Wastage=Energy Input-Energy Output=1500J-1400J=400J</em>
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Hence, the TV has wasted of 26.6%
The formula for calculating the current flowing in a circuit is:
I = V /R
Where:
I = current = ?
V = voltage = 60 V
R = resistance = 12 Ohms
I = V /R = 60/ 12 = 5
Therefore, the current flowing through the circuit is 5 A.