Question

У мережу з напругою 120 В послідовно увімкнені дві лампи, перша з опором 400 Ом, друга з опором 100 Ом. У якій лампі за один й той самий час буде виділятися більша кількість теплоти?

Answer 1

Дано:
U=120В
R1=400 Ом
R2=100 Ом
t=10с
Q1/Q2-?
Q=I²*R*t
I1=U/R1
I2=U/R2
I1=120/400=0.3A
I2=120/100=1.2A
Q1=I²1*R1*t
Q1=0.3²*400*10=0.09*4000=360Дж
Q2=I²2*R2*t
Q2=1.2²*100*10=1440Дж
Q1<Q2

Answer 2

Calculation of Power in Each Lamp

To determine which lamp will produce more heat, we need to calculate the power dissipated in each lamp. The power dissipated in a circuit can be calculated using the formula:

Power (P) = (Voltage (V))^2 / Resistance (R)

Let's calculate the power dissipated in each lamp.

For the first lamp with a resistance of 400 Ω: - Voltage (V) = 120 V - Resistance (R) = 400 Ω

Using the formula, we can calculate the power dissipated in the first lamp:

Power (P1) = (120 V)^2 / 400 Ω

For the second lamp with a resistance of 100 Ω: - Voltage (V) = 120 V - Resistance (R) = 100 Ω

Using the formula, we can calculate the power dissipated in the second lamp:

Power (P2) = (120 V)^2 / 100 Ω

Comparison of Power Dissipation

Now, let's compare the power dissipated in each lamp to determine which one will produce more heat.

Comparing the two power values, we can see that P1 > P2. This means that the first lamp, with a resistance of 400 Ω, will dissipate more power and therefore produce more heat than the second lamp with a resistance of 100 Ω.

Therefore, in the first lamp, more heat will be generated in the same amount of time compared to the second lamp.

Please note that the power dissipated in a circuit depends on the resistance and voltage. In this case, the lamp with a higher resistance will dissipate more power and produce more heat.

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