Una fuente luminosa de 75 W consume 75W de potencia electrica. Suponga que toda la energía se transforma en luz emitida de 600 nm de longitud de onda. a) Calcule la frecuencia de la luz emitida
b) ¿Cuántos fotones por segundo emite la fuente?

Aperson stands on a platform, initially at rest, that can rotate freely without friction. the moment of inertia of the person plus the platform is ip. the person holds a spinning bicycle wheel with its axis horizontal. the wheel has moment of inertia iw and angular velocity ωw. take the ωw direction counterclockwise when viewed from above. part a what will be the angular velocity ωp of the platform if the person moves the axis of the wheel so that it points vertically upward?

Are formed where bumps from two surfaces come into contact ?

A15 ohm resistor and a 25 ohm resistor are connected in parallel to a 60 volt battery. what is the power used by each device