Question

Three blocks of masses $m_{1},m_{2}$ and $m_{3}$ are placed on a horizontal frictionless surface. A force of $40 \, N$ pulls the system then calculate the value of $T$ , if $m_{1}=10 \, kg, \, m_{2}=6 \, kg, \, ⁡m_{3}=4 \, kg$ .

• A. $40 \, N$
• B. $20 \, N$
• C. $10 \, N$
• D. $5 \, N$

Answer 1

Answer: (B)

$a=\frac{F}{m_{1} + m_{2} + m_{3}}$
$a=\frac{40}{10 + 6 + 4}$
$a=2 \, m \, s^{- 2}$
taking blocks of masses $m_{2}$ and $m_{3}$ as a system,
$40-T=10\times 2$
$T=20 \, N$