Un estibador se ha dado cuenta que se requiere una fuerza horizontal de 60lb. Se percata de que una caja mas pequeña del mismo material puede ser arrastrada con rapidez constante con una fuerza horizontal de solo 40 lb ¿cuál es el peso de la caja?

The rigid beam is supported by the three suspender bars. bars ab and ef are made of aluminum and bar cd is made of steel. if each bar has a cross-sectional area of 450 mm2, determine the maximum value of p if the allowable stress is (σallow)st = 200 mpa for the steel and ( σallow)al = 150 mpa for the aluminum. est = 200 gpa and eal = 70 gpa.

Which of the following is tru about semi-conductors

The doctor lands his tardis on a planet whose radius is 1.2x10^7m the acceleration due to gravity is 18m/s^2. what is the mass of the planet