54:29 If the kinetic and potential energy in a system are equal, then the potential energy increases. What happens as a result?

Total energy increases.
Stored energy decreases.
Energy of motion decreases.
Total energy decreases.

the old alchemists made significant contributions to science even though there starting premises were off a bit. their conclusions after failure would steer them into better directions for investigation. science is no more than close observation and the initial mistakes result in rethinking and retrying experiments.

nuclear fission produces elements that are heavier than helium.

the elements that are used in nuclear fission and their products are much heavier than helium.

how important do you think an instrument is to the musician who plays it?