A Nichrome heater dissipates 526 W when the applied potential difference is 110 V and the wire temperature is 800oC. What would be the dissipation rate if the wire temperature were held at 200oC by immersing the wire in a bath of cooling oil? The applied potential difference remains the same, and α for Nichrome at 800oC is 4.0 × 10-4 K-1.

As you are trying to move a heavy box of mass m, you realize that it is too heavy for you to lift by yourself. there is no one around to , so you attach an ideal pulley to the box and a massless rope to the ceiling, which you wrap around the pulley. you pull up on the rope to lift the box. use g for the magnitude of the acceleration due to gravity and neglect friction forces. once you have pulled hard enough to start the box moving upward, what is the magnitude f of the upward force you must apply to the rope to start raising the box with constant velocity? express the magnitude of the force in terms of m, the mass of the box.

At what time will the interfering waves have an amplitudeof zero?

If a star is moving toward earth, it is