A student uses a force meter with a zero error. The same constant pulling force is used in two trials. Work done is calculated independently using an energy sensor.
| Trial | Distance | Work done |
|---|---|---|
| P | 0.40 m | 1.2 J |
| Q | 0.90 m | 2.7 J |
The force meter reads 3.4 N during both trials. What does the force meter read when no force is applied?
6.4 N6.4\ \mathrm{N}6.4 N
0.4 N0.4\ \mathrm{N}0.4 N
3.0 N3.0\ \mathrm{N}3.0 N
1.5 N1.5\ \mathrm{N}1.5 N