A painter of mass M stands on a platform of mass m and pulls himself up by two ropes which hang over pulley as shown in the figure. He pulls each rope with force F and moves upward with a uniform acceleration a. Find a, neglecting the fact that no one could do this for long time.

Question

A painter of mass M stands on a platform of mass m and pulls himself up by two ropes which hang over pulley as shown in the figure. He pulls each rope with force F and moves upward with a uniform acceleration a. Find a, neglecting the fact that no one could do this for long time. (A) (4 F+(2 M+m) g/M+2 m) (B) (4 F+(M+m) g/M+2 m) (C) (4 F-(M+m) g/M+m) (D) (4 F-(M+m) g/2 M+m)

Tardigrade Admin · Accepted Answer

From the figure 2 F+N-M g=M a 2 F-m g-N=m a 4 F-(M+ m) g=(M +m) a a=(4 F-(M+ m) g/M+ m)

Q. A painter of mass $M$ stands on a platform of mass $m$ and pulls himself up by two ropes which hang over pulley as shown in the figure. He pulls each rope with force $F$ and moves upward with a uniform acceleration $a$ . Find $a$ , neglecting the fact that no one could do this for long time.

$\frac{4 F + ( 2 M + m ) g}{M + 2 m}$

$\frac{4 F + ( M + m ) g}{M + 2 m}$

$\frac{4 F - ( M + m ) g}{M + m}$

$\frac{4 F - ( M + m ) g}{2 M + m}$

From the figure
$2 F + N - M g = M a$
$2 F - m g - N = ma$
$4 F - (M + m) g = (M + m) a$
$a = \frac{4 F - ( M + m ) g}{M + m}$

Q. A painter of mass M stands on a platform of mass m and pulls himself up by two ropes which hang over pulley as shown in the figure. He pulls each rope with force F and moves upward with a uniform acceleration a. Find a, neglecting the fact that no one could do this for long time.

M+2m4F+(2M+m)g​

M+2m4F+(M+m)g​

M+m4F−(M+m)g​

2M+m4F−(M+m)g​