Question

A trolley T of mass 5 kg on a horizontal smooth surface is pulled by a load of 2 kg through a uniform rope ABC of length 2 m and mass 1 kg. As the load falls from BC = 0 to BC = 2 m, its acceleration (in m/s²) changes from –

• A. $\frac { 20 } { 6 }$ to $\frac { 30 } { 5 }$
• B. $\frac { 20 } { 8 }$ to $\frac { 30 } { 8 }$
• C. $\frac { 20 } { 5 }$ to $\frac { 30 } { 6 }$
• D. None of these

Answer 1

Answer: (B)

$\frac { 20 } { 8 }$ to $\frac { 30 } { 8 }$

Answer 2

When BC = 0, a; = $\frac { 2 g } { 2 + 1 + 5 }$ = $\frac { 20 } { 8 }$ m/s²

When BC = 2 m ; a' = $\frac { ( 2 + 1 ) g } { 2 + 1 + 5 }$ = $\frac { 30 } { 8 }$ m/s²