Q. 24.3( 4 Votes )

# What is the central angle of the sector to be used to make a cone of base radius 10 centimetres and slant height 25 centimetres?

Answer :

Given that slant height of the cone should be 25 cm.

So radius of the sector r_{s} = 25 cm

To find: Central angle θ

Radius of the base r_{b} = 10 cm

So circumference of the base = 2πr_{b} = 2π×10 = 20π cm ..(1)

This circumference is equal to the length of the arc

The length of arc will be

Thus, the length of arc will be . …(2)

Equating the results in (1) and (2):

⇒ θ = 144°

Rate this question :

How useful is this solution?

We strive to provide quality solutions. Please rate us to serve you better.

Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Expertsview all courses

Dedicated counsellor for each student

24X7 Doubt Resolution

Daily Report Card

Detailed Performance Evaluation

RELATED QUESTIONS :

What is the ratio of the base – radius and slant height of a cone made by rolling up a semicircle?

Kerala Board Mathematics Part-2