Question

A boy uses a vernier callipers to measure the thickness of his pencil. He measures it to be 1.4 mm. If the zero error of vernier callipers is + 0.02 cm, what is the correct thickness of pencil?

• A. 1.3 mm
• B. 1.2 mm
• C. 1.02 mm
• D. 1.20 mm

Answer 1

The correct option is B 1.2 mm

Correct thickness of pencil $=$ measured thickness of his pencil 1.4 mm – correction
Correct thickness of pencil $=$ 1.4 mm – (+0.02 cm)
Correct thickness of pencil $=$ 1.4 mm – (+0.2 mm)
Correct thickness of pencil $=$ 1.4 mm – 0.2 mm
Correct thickness of pencil $=$ 1.2 mm