Atypical photovoltaic cell delivers 4.2×10−3 w of electric energy when illuminated with 0.15 w of light energy. what is the efficiency of the cell?

Energy is the ability to do work which measures what

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)

Anoche fuimos al restaurante el gusto. jaime le (1) (pedir) al camarero una mesa en la sección de no fumar. yo (2) (pedir) chuleta de cerdo con champiñones, papas y ensalada y jaime (3) (pedir) mariscos, arroz y ensalada. el restaurante estaba lleno (full) por eso no nos (4) (servir) muy rápido (very fast), pero la comida estaba deliciosa. no me lo vas a creer (you won't believe it) pero ¡jaime (5) (repetir) arroz y mariscos! ¡dos porciones (orders)! ¿ya entiendes por qué él no (6) (dormir) bien anoche?