Question

One end of a string is attached to a 4 kg mass undergoing velocity v₁ = 5 m/s at a radius of r₁ = 500 mm on a frictionless table.  The other end of the string passes through a hole in the table.  Find the velocity v₂ of the mass if the string is slowly (assume v_r ~ 0) pulled through the hole until its radius is r₂ = 200 mm.

3 ms 500 mm

Answer 1

Initial angular momentum Vini = 4 x 5 x 0.5 m 10kg m²/sec tiñal angulas momentum m V2 se 4 x V x 0,2 0.8 ve kg m’lsec external torque cuas acting on no As system 0,8 V 2 100 112.5 mlsec = 1 V2 = 8