ENEM 2024 PPL - Ao realizar os preparativos para o Natal, uma pessoa resolveu aumentar o número de

(ENEM/PPL 2024) When preparing for Christmas, a person decided to increase the number of incandescent bulbs in a string of lights that originally had 20 bulbs connected in parallel, each with resistance R. He added another 20 bulbs with the same specifications and also in parallel. The circuit now consists of 40 bulbs in parallel and a source of internal resistance r. The total current of the circuit with 40 bulbs is proportional to the current of the circuit with 20 bulbs, that is, i40 = α ∙ i20. When turning on the system, he noticed that the brightness of the bulbs decreased with a proportionality factor equal to α2. What is the factor α used to obtain the reduction in brightness in each bulb? 1/2 1/20 (R/20+r)/(R/40+r) (R/40+r)/(R/20+r) R/40 + r ================== Follow us on social media: 📱 Instagram:   / thalesquirino   📱 Twitter: https://x.com/fisiquei Check out the complete playlist by 👉 Professor Thales Quirino Medeiros ================== #ENEM #physics #medicine #studies #education