One end of 12 m long rubber tube with a total mass of 0.9 kg is fastened to a fixed support. A cord attached…
One end of 12 m long rubber tube with a total mass of 0.9 kg is fastened to a fixed support. A cord attached to the other end passes over a pulley and supports an object with a mass of 5 kg. The tube is struck to a transverse blow at one end. Find the time required for the pulse to reach the other end. (Take, g = 9.8 ms^-2)
Solution
Sol. Tension in the rubber tube AB,
T = mg or T = (5.0) (9.8) = 49 N
Mass per unit length of rubber tube,
α = 0.9/12 = 0.075 kg m^-1
∴ Speed of wave on the tube,
v = √(T/α) = √(49/0.075) = 25.56 ms^-1
∴ The required time,
t = AB/v = 12/25.56 = 0.47 s
Answer: t = 0.47 s