Motion in a circle

Answer Key - Grade 11 Science Worksheet

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

1. 1.

   A 2 kg cart runs around a circular track of radius 1.5 m at a steady 3 m/s. What force toward the center does it need, Ari?

   12 N
2. 2.

   A 0.2 kg cart runs around a circular track of radius 0.9 m at a steady 6 m/s. What force toward the center does it need, Bo?

   8 N
3. 3.

   A cart goes once around a circular track of radius 2 m in 4 s. What is its speed, Jun?

   • About 1.57 m/s
   • 0.5 m/s
   • About 3.14 m/s
4. 4.

   A ball on a 0.5 m string goes around 2 times each second. What is its speed, Kira?

   • About 3.14 m/s
   • 1 m/s
   • About 6.28 m/s
5. 5.

   A cart's time for one lap doubles on the same track. What happens to its speed, Luz?

   • It doubles
   • It stays the same, since the track is the same
   • It halves
6. 6.

   A cart on a circular track doubles its speed. What happens to the force it needs toward the center, Milo?

   • It halves
   • It is 4 times as big
   • It doubles
7. 7.

   A cart keeps the same speed but moves to a track with twice the radius. What happens to the force it needs, Noah?

   • It is 4 times as big
   • It doubles
   • It halves

8. Read this first

   Carts on circular tracks (example data)

   Cart	Mass (kg)	Speed (m/s)	Radius (m)
   A	1	2	1
   B	1	4	2
   C	2	2	2

9. 8.

   Using the table, which cart needs the biggest force toward the center, Ren?

   • Cart B, at 8 N
   • Cart C, since it is heaviest
   • Cart A, on the tightest track
10. 9.

    Using the table, which two carts need the same force, Tala?

    • B and C, on the same radius
    • A and C, at 4 N each
    • A and B, with the same mass
11. 10.

    Using the table, what is cart B's acceleration toward the center, Zee?

    • 8 m/s²
    • 16 m/s²
    • 2 m/s²