The four fundamental forces

Answer Key - Grade 11 Science Worksheet

Circle the best answer, or write your answer on the line.

1. 1.

   Two protons are 2 × 10⁻¹⁵ m apart. With k = 8.9875 × 10⁹ N·m²/C² and e = 1.602176634 × 10⁻¹⁹ C, what electric force pushes them apart, to 0.01 N, Ari?

   57.68 N
2. 2.

   Two protons are 3 × 10⁻¹⁵ m apart. With k = 8.9875 × 10⁹ N·m²/C² and e = 1.602176634 × 10⁻¹⁹ C, what electric force pushes them apart, to 0.01 N, Bo?

   25.63 N
3. 3.

   Two protons are 4 × 10⁻¹⁵ m apart. With k = 8.9875 × 10⁹ N·m²/C² and e = 1.602176634 × 10⁻¹⁹ C, what electric force pushes them apart, to 0.01 N, Esme?

   14.42 N
5. 4.

   Using the table, about how many times stronger is the strong force than the weak force, Kira?

   • About 137 times as strong
   • About 6 times
   • About a million times
6. 5.

   Using the table, which force is about 137 times weaker than the strong force, Luz?

   Use the picture in question 4.

   • Electromagnetic
   • The weak nuclear force
   • Gravity
7. 6.

   Protons in a nucleus push each other apart. What holds the nucleus together, Milo?

   • Gravity between the many protons
   • The strong force, at short range
   • The weak force pulling them in
8. 7.

   Why doesn't the strong force pull a cup toward a table, Noah?

   • Cups and tables don't contain protons
   • Its range is about a nucleus wide
   • It is weaker than gravity
9. 8.

   Why are very large nuclei less stable than middle-sized ones, Pia?

   • Their electrons pull them apart
   • Big nuclei have no neutrons
   • The electric push reaches farther
10. 9.

    Which particles carry the weak force, Tala?

    • Photons
    • Protons
    • W and Z bosons
11. 10.

    Which particle carries the strong force between quarks, Zee?

    • The gluon
    • The electron
    • The photon