How does the brightness of a bulb tell you about the energy of electrons passing through it?

Natural forces that can alter ecosystems include seasons and climate changes. t or f

Acave rescue team lifts an injured spelunker directly upward and out of a sinkhole by means of a motor-driven cable. the lift is performed in three stages, each requiring a vertical distance of 10.0 m: (a) the initially stationary spelunker is accelerated to a speed of 4.90 m/s; (b) he is then lifted at the constant speed of 4.90 m/s; (c) finally he is decelerated to zero speed. how much work is done on the 68.0 kg rescue by the force lifting him during each stage?

Within a pendulum, as potential energy decreases, energy increases. a. heat b. kinetic c. frictional d. gravitational