wiz-icon
MyQuestionIcon
MyQuestionIcon
5
You visited us 5 times! Enjoying our articles? Unlock Full Access!
Question

Length of the minute hand in a clock is 10 cm. Find difference between average speed and magnitude of average velocity (in cm/min) of tip of the minute hand from 6 a.m. to 6:20 a.m.

A
2π332
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
2π312
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
π332
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D
π312
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is C π332

Given time, t=20 min
The distance covered by minute hand
d=rθ, where r is the length of the minute hand and θ in radians.

θ=120=π180×120 rad=2π3 rad
d=10×2π3 cm
Average speed:
v=dt=20π3×20=π3 cm/min

Displacement: D=2rsinθ2
D=2×10×sin1202=103 cm
Magnitude of average velocity:
V=Dt=10320=32 cm/min

The difference is : π332 cm/min

flag
Suggest Corrections
thumbs-up
1
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Speed and Velocity
PHYSICS
Watch in App
Join BYJU'S Learning Program
CrossIcon