Question

The two crates m 2 = 40 kg and m 1 = 60 kg are to be accelerated upward to a ship at the rate of 0.30 m/s ^ 2 Determine the tension in each rope.

Answer 1

According to the second Newton's law, the tension $T$ in a cord is:

$$T = ma$$

where $m$ is the mass of a crate and $a$ is its acceleration. Thus, for the first crate have:

$$T_1 =m_1a = 60kg\cdot 0.3m/s^2 = 18N$$

And for the second

$$T_2 =m_2a = 40kg\cdot 0.3m/s^2 = 12N$$

Answer. $T_1 = 18N,\space T_2 = 12N.$