A system to 10 balls each of mass 2 kg are connected via massless and unstretchable string. The system is allowed to slip over the edge of a smooth table as shown in figure. Tension on the string between the 7th and 8th ball is ______ N when 6th ball just leaves the table.
Fig. Tension on String
A system to 10 balls each of mass 2 kg are connected via massless and unstretchable string. The system is allowed to slip over the edge of a smooth table as shown in figure. Tension on the string between the 7th and 8th ball is ______ N when 6th ball just leaves the table.
Correct Answer: 36
Solution and Explanation
The correct answer is 36N
At given instant
\(a_{sys} = \frac{6m × g }{ 10m} = \frac{6g}{100}\)
\(∴ T_{78} = ( 3m ) × a_{sys} \)
\(= ( 3m ) × ( \frac{6g}{100} )\)
\(= \frac{3 × 2 × 6 × 10 }{10} \)
\(= 36N\)
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Concepts Used:
Tension
A force working along the length of a medium, especially if this force is carried by a flexible medium like cable or rope is called tension. The flexible cords which bear muscle forces to other parts of the body are called tendons.
Net force = 𝐹𝑛𝑒𝑡 = 𝑇−𝑊=0,
where,
T and W are the magnitudes of the tension and weight and their signs indicate a direction, be up-front positive here.
Read More: Tension Formula