Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Numerical Ability

Topic

Time, Speed and Distance

Question:

A field roller in the shape of a cylinder, has a diameter of 2 m and length of 2\(\frac{1}{4}\)m.  If the  speed at which the roller rolls is 14 revolution per minute, then the maximum area (in m2) that it can roll in 1 hour is? (take \(\pi \) = \(\frac{22}{7}\))

Options:

11088

11880

11808

11110

Correct Answer:

11880

Explanation:

radius = \(\frac{2}{2}\) = 1 meter

height = \(\frac{9}{4}\) meter

Area covered in one revolution = 2\(\pi \)rh (L.S.A.)

Area covered in one minute = 2\(\pi \)rh × 14

= 2 × \(\frac{22}{7}\) × 1 × \(\frac{9}{4}\) × 14 = 198

Area covered in 1 hour = 198 × 60 = 11880