Prediction Consider just the heavier block (m1), which will fall from rot to the
ID: 1950052 • Letter: P
Question
Prediction Consider just the heavier block (m1), which will fall from rot to the floor in each trial. Do you predict that its mechanical energy E1 will increase, decrease, or be conserved while it falls? Why? Consider just the lighter block (m2), which will rise from rest into the air in each trial. Do you predict that its mechanical energy E; will increase, decrease, or be conserved while it rises? Why? Now consider both blocks as a system with two moving parts, one rising from rest and one falling from rest Do you predict that the system's mechanical energy E = E1 + E2 will increase, decrease, or be conserved in these trials? Why?Explanation / Answer
-the heavier block will lose m1gh of potential energy, but not all of this will be converted into it's KE because it will be used to raise the second block. Thus, the block will lose mechanical energy. -the lighter block will gain m2gh of potential energy, and will also gain kinetic energy from the pull of the heavier block. Thus, it will gain mechanical energy. -The system's mechanical energy will only change if there is work being done on the system. In this case, gravity does work on the heavier block = m1gh, it also does negative work on the lighter block = - m2gh. m1 > m2, thus, the amount of work done is positive. Therefore the system will gain mechanical energy.