Wood has chemical energy, which can be used to generate thermal and radiant energy when burned in a fireplace. Which best explains what happens to the total amount of energy in this scenario? The total energy in the system increases because chemical energy creates thermal and radiant energy. The total energy in the system decreases because chemical energy disappears as thermal and radiant energy are generated. The total energy in the system remains the same as the decrease in chemical energy equals the increase in thermal and radiant energy. The total energy in the system remains the same as the increase in chemical energy equals the decrease in thermal and radiant energy.

A50 kg student climbs 3 m to the top of a set of stairs. calculate the change in the student’s gravitational potential energy from the bottom to the top of the stairs. show your calculations and include units in your answer. how much total work does the student do while climbing the stairs? show your calculations or explain your reasoning. include units in your answer. it takes the student 30 s to climb to the top of the stairs. what is the average power generated by the student climbing the stairs? show your calculations and include units in your answer. the next day the student carries a 10 kg backpack up the same stairs and again takes 30 s to reach the top of the stairs. is the average power you calculated in part (c) greater than, less than, or equal to the average power the student generated the next day? explain your answer.