The four fundamental forces
Grade 11 Science Worksheet - Challenge Me
Circle the best answer, or write your answer on the line.
A nucleus of 64 nucleons has radius 1.2 × ∛64 fm. Protons 1 fm apart repel with 230.7 N. What force do two protons on opposite sides feel, to 0.01 N, Bo?
A nucleus of 125 nucleons has radius 1.2 × ∛125 fm. Protons 1 fm apart repel with 230.7 N. What force do two protons on opposite sides feel, to 0.01 N, Esme?
Jun says gravity must be the strongest force because it holds galaxies together. Agree or disagree?
- Agree: galaxies show that gravity is the strongest
- Agree: it beats the strong force
- Disagree: it is weakest, but mass adds up
Kira says the strong force must also pull on the Moon. Agree or disagree?
- Agree: it keeps the Moon in orbit
- Agree: it is the strongest force
- Disagree: its range is far too short
Luz says friction isn't a fifth fundamental force; it comes from electromagnetism. Agree or disagree?
- Disagree: it comes from the weak force
- Agree: it comes from charges in atoms
- Disagree: it is a fifth fundamental force
Two protons are 1 fm apart. Which is bigger, the electric push or the gravity pull, Milo?
- The gravity pull, by about 10³⁶ times
- The gravity pull, by a little
- The electric push, by about 10³⁶ times
At 1 fm, the strong pull between two protons beats their electric push. What happens at 3 fm, Noah?
- Gravity takes over and pulls them in
- The strong pull grows much stronger
- The strong pull fades; the push wins
Why can gravity hold a star together when the electric force is far stronger, Pia?
- Its charges cancel; its mass doesn't
- Stars contain no atoms
- Electric forces stop working in space
Why does the Sun use up its hydrogen slowly, over billions of years, Tala?
- Gravity stops most of the Sun's reactions
- Its core is too cold for fusion
- Its first step relies on the weak force
Which force squeezes the Sun's core hot and dense enough for fusion, Zee?
- Gravity
- Friction
- The weak force