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Newton's laws and weightPhysicsHigh schoolabout 0:48

A 3 kg cart accelerates at 5 m/s². What net force acts on it?: animated lesson

A narrated, step-by-step newton's laws and weight video lesson with captions. Final answer: net force F = 15 N.

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Video with a synthetic English voice and captions. Pick another language for subtitles in that language, or open the interactive version.

Video narrated by a synthetic voice (Piper TTS, en_US-ljspeech-high voice (LJ Speech dataset, public domain)); the steps come from our maths engine and the answer was checked independently. Download MP4 (0.3 MB) · Captions (WebVTT)

Steps on screen

1. The problem
Worked example
A 3 kg cart accelerates at 5 m/s². What net force acts on it?
2. Step by step
1. $F = ma$
  Formula: Newton's second law
2. $F = (3\ \text{kg})\cdot (5\ \text{m/s²}) = 15\ \text{N}$
  Substitute the known values
3. The answer
$\text{net force F = 15 N}$
net force F = 15 N
4. Check
- Substituted every value back into the formula: both sides agree ✓

Transcript

The problem. Here is the problem: A 3 kg cart accelerates at 5 m/s squared. What net force acts on it? Use the Newton prime s second law formula, rearranged for the unknown, in SI units.

Step by step. Formula: Newton prime s second law. Substitute the known values.

The answer. So the answer is net force F equals 15 N. 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.

Check. Substituted every value back into the formula: both sides agree, which checks out.

About newton's laws and weight

Use F = ma and W = mg to find force, mass, acceleration and weight.

A 3 kg cart accelerates at 5 m/s². What net force acts on…