NCERT Solutions for Class 9th Science Chapter 6 .5 Newton's Second Law of Motion — Threads of Curiosity

Book page 1046 Updated on2026-09-08

Q1.
How much does a force of 1 N feel?
Answer

About the weight of a 100 g mass resting in your palm — a small apple, or a standard 100 g packet.

m = 100 g = 0.1 kg, g = 9.8 m s–2
Weight, F = mg
F = 0.1 kg × 9.8 m s–2
F = 0.98 N ≈ 1 N

The mass presses down on your palm with about 1 N, and your palm pushes it back up with about 1 N. The two forces balance, which is why the mass stays at rest.

Why this is worth knowing: newtons only become real when you can feel one. Once "1 N ≈ the pull of a 100 g mass" is fixed in your mind, the numbers in problems stop being abstract — a 3000 N force on a sports car is the weight of about 300 kg, and a 500 N stopping force on a bullet is enormous for something of mass 50 g.
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