Question

A body of mass 1 kg tied to one end of string is revolved in a horizontal circle of radius 0.1 m with a speed of 3 revolution/sec, assuming the effect of gravity is negligible, then linear velocity, acceleration and tension in the string will be :

• A. 1.88 m/s, 35.5 m/ $ I=100\sin 200\pi t $ , 35.5 N
• B. 2.88 m/s, 45.5 m/ $ \frac{1}{400}s $ , 45.5N
• C. 3.88 m/s, 55.5 m/ $ \frac{1}{300}s $ , 55.5N
• D. none of these

Answer 1

Answer: (A)

Here: mass of the body = 1 kg Radius of circle = 0.1 m n = 3 rev/sec Hence, angular speed $ \omega =2\pi \times 3=6\pi \,rad/\sec $ (1) linear speed $ \upsilon =r\omega =0.1\times 6\times 3.14=1.88m/s $ (2) acceleration $ a=r{{\omega }^{2}}=0.1\times {{(6\pi )}^{2}}=35.5m/{{s}^{2}} $ (3) tension in strip $ T=mr{{\omega }^{2}}=1\times 0.1\times {{(6\pi )}^{2}}=35.5N $