Question

In which of the following cases , the net force is zero?
I) A ball freely falling from a certain height
II) A cork floating on the surface of water
III) An object floating in air

• A. I and II only
• B. II and III only
• C. III and I only
• D. I, II and III

Answer 1

The correct option is B II and III only

$\begin{array}{c}\text{In first case gravity is there so net fore is}\\ \text{not zero? while in others it is balanced by}\\ \text{buoyancy of air and liquid.}\\ \text{so net force is zero in II,}III\text{case}\\ \text{so Ans is (B).}\end{array}$