WEBVTT

1
00:00:00.000 --> 00:00:06.827
Here is the problem: A 40 kg cart accelerates at 2 m/s squared. What net force acts on it?

2
00:00:07.277 --> 00:00:13.291
Use the Newton prime s second law formula, rearranged for the unknown, in SI units.

3
00:00:14.091 --> 00:00:16.947
Formula: Newton prime s second law.

4
00:00:17.397 --> 00:00:19.371
Substitute the known values.

5
00:00:20.171 --> 00:00:23.573
So the answer is net force F equals 80 N.

6
00:00:24.023 --> 00:00:40.707
Newton prime s second law links the net force on an object to its acceleration: F equals ma. Force and acceleration point the same way, so a negative force gives a negative acceleration. One newton accelerates one kilogram by 1 m/s squared.

7
00:00:41.506 --> 00:00:47.114
Substituted every value back into the formula: both sides agree, which checks out.