Un motor d’un cotxe ens dóna 100 CV.   Si el rendiment és del 32,5 %, quina és la potència consumida en watts?

Una empresa fabricant de cintes transportadores ens ha contractat com a aprenents d’enginyers. La nostra primera tasca és la de trobar un motor per fer funcionar una cinta transportadora que fa 5 m fent una força de 1929 N. Volem que aquest moviment es realitzi en 40 s.  Si sabem que els motors elèctrics tenen un rendiment de 85 %, quina potència consumirà el nostre motor?

A una estación de servicios llegan usuarios con una tasa de 45 usuarios cada 60 minutos, si la llegada de usuarios a dicha estación sigue una distribución Poisson, responda las siguientes preguntas:

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Hay 80 aspirantes, (mujeres, M y hombres, H) para un trabajo, 20 son integrantes del grupo A, 25 del grupo B y 35 del grupo C. Los números de mujeres (M) en los tres grupos son 4 en el grupo A, 14 en el grupo B y 24 en el grupo C. Una persona es seleccionada al azar para cubrir el puesto. Calcule las sguientes probabilidades:

Avui per esmorzar hem menjat 20800 J. Si el nostre organisme té un rendiment del 28% en esforç muscular i hem anat a escalar, quants metres podrem pujar per “cremant” tot l’esmorzar si pesem 79 Kg? (Sense fregaments.)