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Newton's laws and weightPhysicsMiddle schoolabout 0:50

What is the weight of a 2.5 kg object on Earth (g = 9.81 m/s²)?: animated lesson

A narrated, step-by-step newton's laws and weight video lesson with captions. Final answer: weight W = 24.525 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
What is the weight of a 2.5 kg object on Earth (g = 9.81 m/s²)?
2. Step by step
1. $W = mg$
  Formula: weight
2. $W = (2.5\ \text{kg})\cdot (9.81\ \text{m/s²}) = 24.525\ \text{N}$
  Substitute the known values
3. The answer
$\text{weight W = 24.525 N}$
weight W = 24.525 N
4. Check
- Substituted every value back into the formula: both sides agree ✓

Transcript

The problem. Here is the problem: What is the weight of a 2.5 kg object on Earth (g equals 9.81 m/s squared)? Use the weight formula, rearranged for the unknown, in SI units.

Step by step. Formula: weight. Substitute the known values.

The answer. So the answer is weight W equals 24.525 N. Weight is the gravitational force on a mass: W equals mg, with g approximately 9.81 m/s squared near Earth prime s surface (1.62 m/s squared on the Moon). Mass in kilograms does not change from place to place; weight in newtons does.

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.

What is the weight of a 2.5 kg object on Earth (g = 9.81…