An inclined plane is constituted by a wooden board 3 m long and is placed to raise a 80 N rock to a height of 1.4 m. The force required to raise the rock is 45 N. Answer items a), b) and c). a) Calculate the ideal mechanical advantage of the inclined plane
b) Calculate the real mechanical advantage of the inclined plane
c) Calculate the efficiency of the inclined plane.

In a sample of oxygen gas at room temperature, the average kinetic energy of all the balls stays constant. which postulate of kinetic molecular theory best explains how this is possible? a. attractive forces between gas particles are negligible because the particles of an ideal gas are moving so quickly. b. collisions between gas particles are elastic; there is no net gain or loss of kinetic energy. c. gases consist of a large number of small particles, with a lot of space between the particles. d. gas particles are in constant, random motion, and higher kinetic energy means faster movement.

In an exothermic reaction the bonding energy of the product is: less than the reactants same as the reactants greater than the reactants dependent upon the presence of a catalyst

The reactions of photosynthesis occur in the of plant cell? a.mitochondria. b. lysosomes. c. chloroplasts. d. chlorophyll