question: Compared with the mass of a uranium atom undergoing fission, the combined masses of the products after fission are

options:
- less
- more
- the same
- zero


question: Things that are equivalent according to the equivalence principle are

options:
- space and time.
- a traveling twin and a stay-at-home twin.
- gravity and acceleration.
- mass and energy.


question: Colors in a soap bubble result from light

options:
- converted to a different frequency
- deflection
- interference
- polarization


question: A model airplane flies slower when flying into the wind and faster with wind at its back. When launched at right angles to the wind a cross wind its groundspeed compared with flying in still air is

options:
- the same
- greater
- less
- either greater or less depending on wind speed


question: Which of these three elements has the most mass per nucleon?

options:
- Hydrogen
- Iron
- Uranium
- Same in each