Question

An insect trapped in a circular groove of radius 12 cm moves along the groove steadily and completes 7 revolutions in 100 s The angular speed and linear speed of the motion are

• A. $0.11 \,rad / s , 3.4\, cm \,s ^{-1}$
• B. $0.22\, rad / s , 4.6\, cm \,s ^{-1}$
• C. $0.44 \,rad / s , 5.3 \,cm \,s ^{-1}$
• D. $0.66\, rad / s , 6.4 \,cm\, s ^{-1}$

Answer 1

Answer: (C)

$ \omega=\frac{2 \pi}{T}=\frac{2 \pi \times 7}{100}=0.44 \frac{ rad }{ s }$
$v=\omega R=0.44 s ^{-1} \times 12\, cm =5.3 \,cm \,s ^{-1}$