Astudent pulls a rope attached to a box of books and moves the box down the hall. the student pulls with a force of 175n at an angle of 25.0º above the horizontal. the box has a mass of 35.0 kg and the coefficient of kinetic friction between the box and the floor is 0.280. find the acceleration of the box. 1.65 m/s² 2.38 m/s² 3.72 m/s² 9.37 m/s² four forces act on a hot air balloon as shown below. find the magnitude and direction of the resultant force on the balloon. show your work and explain your answer

Acoal-fired plant generates 600 mw of electric power. the plant uses 4.8 x 10^6 kg of coal each day, and the heat of combustion of coal is 3.3x 10^7 j/kg. the steam that drives the turbines is at a temperature of 300° c, and the exhaust water is at 37° c. (a) what is the overall efficiency of the plant for generating electric power? (b) how much thermal energy is exhausted each day? (c) what is the change in entropy of the universe for this heat engine? (d) using the same heat reservoirs, what is the maximum possible (carnot) efficiency for a heat engine?

What is the scientific definition of energy that relates to work

Researchers determine that the biodiversity in a woodland region is declining. they identify two major threats to the region's biodiversity, a method to address each threat, and the expected outcome of each method. this information is shown in the table. a) reforestation would not benefit many species because most forest species live on the ground. b) reforestation would take the longest time to be effective because trees take several years to grow. c) biological augmentation would benefit only a few species because is is typically not very effective. d) biological augmentation would take less time to ve effective because it targets the majority of prey species.