Un grúa cuyo rendimiento es del 50% está instalada a un motor cuyo rendimiento es del 80%. Si al motor se le proporciona una potencia de 800watt, calcular la velocidad constante con la cual podrá subir un bloque e masa 1kg (g = 10m/s2

show the wavelengths of a wave. show the crests of a wave.

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.

elctricity and magnet is conversion to it