Se le aplica una tensión de 61 N a una piedra que se encuentra sobre una superficie en presencia de fricción. Si la masa de la piedra es de 44 kg. Encuentre el coeficiente de fricción estático entre la piedra y la superficie. Exprese su resultado con 2 cifras significativas.

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 11.0 m: (a) the initially stationary spelunker is accelerated to a speed of 4.80 m/s; (b) he is then lifted at the constant speed of 4.80 m/s; (c) finally he is decelerated to zero speed. how much work is done on the 78.0 kg rescue by the force lifting him during each stage

Which wave is the result of amplification and produces a louder sound

Why should the wavelength scale of spectroscope be calibrated