Question

An air balloon accelerates upward at a rate of 1.1 m/s ^2 . If the flames produce an upward force of 2300 N, what is the mass of the air balloon?

Answer 1

Explanations & Calculations

• The balloon has an acceleration upwards thus an unbalanced force should be acting along that direction.
• Therefore, applying Newton's second law on the balloon upwards, the (needed) mass of the balloon can be found.
• Identify all the forces acting on the balloon before applying the equation

weight of the ballon downwards: towards the ground

Force generated on the balloon upwards

• Then,

$\qquad\qquad \begin{aligned} \small \uparrow F&= \small ma\\ \small \uparrow2300\,N-\downarrow mg&= \small ma\\ \small m&= \small \frac{2300\,N}{g+a}=\frac{2300\,N}{9.8+1.1}\\ &= \small \bold{211.009}\,kg \end{aligned}$