Question

A uniform thick rope of length $5m$ is kept on frictionless surface and a force of $5N$ is applied to one of its end. Find tension in the rope at $1m$ from this end-

• A. $1N$
• B. $3N$
• C. $4N$
• D. $5N$

Answer 1

The correct option is C $4N$

Length of the ropeL $=5m$
Let m be the mass of the rope. Mass per unit length of the rope$=\frac{m}{5}$
Acceleration of the rope $a=\frac{F}{m}=\frac{5}{m}$
Mass of the 4 m long rope that tension pulls$M=\frac{4m}{5}$
Tension in the rope at 1 m from the end where force is applied$=Ma$
$=\left(\frac{4m}{5}\right)\times \left(\frac{5}{m}\right)$
$=4N.$