A load of mass $m = 4$ kg is lifted vertically upward with an acceleration of $a = 2$ m/s². Find the tension in the string that the load hangs from. Neglect air resistance; $g = 10$ m/s².
The load accelerates upward, so the tension is greater than the weight. By Newton's second law ($T$ upward, $mg$ downward):
$$T - mg = ma \Rightarrow T = m(g + a)$$
$$T = 4 \cdot (10 + 2) = 4 \cdot 12 = 48 \text{ N}$$
$T = 48$ N