Two persons are holding a rope of negligible mass horizontally. A 20 kg mass is attached to the rope at the mid-point, as a result, the rope deviates from the horizontal direction. The tension required to completely straighten the rope is (g = 10 m/s2)
A. 200 N
B. 20 N
C. 10 N
D. infinitely large
Answer: Option A
Solution (By Examveda Team)
When a mass is attached to the midpoint of a rope held horizontally by two persons, it causes the rope to deviate from the horizontal direction due to the force of gravity acting on the mass. To completely straighten the rope, the tension in the rope must counteract the gravitational force acting on the mass. Since the mass is 20 kg and the acceleration due to gravity (g) is 10 m/s2, the gravitational force on the mass is given by F=mg, where m=20kg and g=10m/s2.Therefore, F=20×10=200N
So, the tension required to completely straighten the rope is
200 N. This Question Belongs to Physics GK Chapter Wise >> Law Of Motion
should be infinitely large