Un generator electric de curent continuu debitează în circuitul exterior aceeași putere P = 4 W dacă, la borne, se conectează un rezistor R1 = 0,01 Ω sau un rezistor R2 = 100 Ω. Determină: valoarea rezistenței interne a generatorului; randamentul circuitului, dacă la borne este cuplat, în locul rezistorilor anteriori, un alt rezistor cu rezistența electrică R3 = 2 Ω; energia electrică disipată pe rezistorul R3, în condițiile punctului b, timp de o oră; valoarea maximă a puterii pe care sursa o poate debita în circuitul exterior, dacă rezistența acestuia are o valoare convenabil aleasă.

4. who was the first one to measure the speed of light and conclude that it is finite? 5. who was the first philosopher who thought the speed of light is finite? 13. what is the speed of light numerically? 14. give an example of something moving faster than light 15. give an example for some particles or waves that

Imagine you are riding on a yacht in the ocean and traveling at 20 mph. you then hit a golf ball at 100 mph from the deck of the yacht. you see the ball move away from you at 100mph, while a person standing on a near by beach would observe your golf ball traveling at 120 mph (20 mph + 100 mph). now imagine you are aboard the hermes spacecraft traveling at 0.1c (1/10 the speed of light) past mars and shine a laser from the front of the ship. you would see the light traveling at c (the speed of light) away from your ship. according to einstein’s special relativity, how fast will a person on mars observe the light to be traveling? a) 0.1c (1/10 the speed of light) b) c (the speed of light) c)1.1c (c+0.1c)

Does anyone have the answers to online physics course plato course physics, semester a v3.0