"How many times are the hour hand and the minute hand of a clock at right angles during their motion
Channel: Doubtnut
Date: 2020-04-05

"How many
 times are the hour hand and the minute hand of a clock at right angles during
 their motion from 1.00 p.m. to 10.00 p.m.?
(a) 9 (b) 10 (c) 18 (d) 20"