A technician investigates the motion of a drone in a vertical test area. The mass of the drone remains constant. For each motor setting, the technician determines the upward resultant force and records the upward acceleration three times.
| Upward resultant force / N\text{N}N | Acceleration 1 / m s−2\text{m s}^{-2}m s−2 | Acceleration 2 / m s−2\text{m s}^{-2}m s−2 | Acceleration 3 / m s−2\text{m s}^{-2}m s−2 |
|---|---|---|---|
| 1.5 | 1.1 | 1.2 | 1.3 |
| 3.0 | 2.3 | 2.5 | 2.4 |
| 4.5 | 3.7 | 3.5 | 3.6 |
| 6.0 | 4.9 | 4.8 | 4.7 |
| 7.5 | 5.9 | 6.1 | 6.0 |
Calculate the mean acceleration when the resultant force is 1.5 N.
Explain what the results show about the relationship between resultant force and acceleration, and how the repeat readings affect confidence in the conclusion.