A heavy ball is suspended as shown in the figure given below. A quick jerk on the lower string will break that string but a slow pull on the lower string will break the upper string. The first result occurs because Lower string

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Q: 59 (NDA-II/2010)
A heavy ball is suspended as shown in the figure given below. A quick jerk on the lower string will break that string but a slow pull on the lower string will break the upper string. The first result occurs because Lower string

question_subject: 

Science

question_exam: 

NDA-II

stats: 

0,5,8,2,1,5,5

keywords: 

{'heavy ball': [0, 0, 1, 0], 'ball': [1, 3, 13, 12], 'upper string': [0, 0, 1, 0], 'lower string': [0, 0, 1, 0], 'inertia': [0, 0, 4, 3], 'string': [0, 0, 2, 2], 'slow pull': [0, 0, 1, 0], 'force': [0, 0, 0, 2], 'air friction': [0, 0, 1, 0], 'quick jerk': [0, 0, 1, 0], 'action': [1, 0, 4, 13], 'reaction': [1, 0, 5, 18]}

The correct answer is option 4: the ball has inertia.

Inertia is the property of an object to resist changes in its motion. When a quick jerk is applied to the lower string, the ball experiences a sudden change in its vertical motion. Due to its inertia, the ball tends to stay at rest and resists the sudden upward motion. As a result, the force applied to the lower string is not enough to overcome the ball`s inertia and move it upward, causing the string to break.

On the other hand, when a slow pull is applied to the lower string, the ball gradually gains momentum and starts moving upward. The force applied to the lower string is distributed over a longer period of time, allowing the ball to gradually overcome its inertia and move upward. This gradual upward motion exerts a stronger force on the upper string, causing it to break instead.

Options 1 and 2 are incorrect as they do not explain the observed phenomenon correctly. Option 3, action and reaction, is not applicable in this scenario since it refers to the equal and opposite forces between two interacting objects.