Una barra de hierro cuya longitud inicial es de 2m se le incrementa su temperatura de 20 °C a 120 °C ¿Cuál es la longitud final de la barra? (considera que el coeficiente de dilatación del hierro) es 1,2 x 10-5 1/°C ( 3 puntos)

Oxygen and nutrients are moved through the body by the: a. circulatory system c. lymphatic system b. digestive system d. reproductive system

As you are trying to move a heavy box of mass m, you realize that it is too heavy for you to lift by yourself. there is no one around to , so you attach an ideal pulley to the box and a massless rope to the ceiling, which you wrap around the pulley. you pull up on the rope to lift the box. use g for the magnitude of the acceleration due to gravity and neglect friction forces. once you have pulled hard enough to start the box moving upward, what is the magnitude f of the upward force you must apply to the rope to start raising the box with constant velocity? express the magnitude of the force in terms of m, the mass of the box.

How many atoms of nitrogen are in the chemical formula ni(w on