Chapter 4, Problem 61A

To determine

The magnitude of the force exerted by the raindrop on Earth.

Answer to Problem 61A

  $\text{2}\text{.4}\times {10}^{-5}\text{N}$

Explanation of Solution

Given:

The mass of the raindrop is $m=2.45\text{ mg}$

Formula used:

Force due to gravity:

  $F_g=mg$

Where, m is the mass and g is the acceleration due to gravity.

Calculation:

The raindrops will execute a free-fall motion, thus only acceleration due to gravity will act on them.

Now, it is known that the acceleration due to gravity on Earth is $g=9.8{\text{m/s}}^{\text{2}}$ .

Then, the force exerted by the raindrop on the Earth will be,

  $\begin{array}{c}{F}_g=\left(m\right)\left(g\right)\\ =\left(\text{2}\text{.45}\times {10}^{-6}\text{kg}\right)\times 9.8\\ =\text{2}\text{.401}\times {10}^{-5}\text{N}\end{array}$

Conclusion:

Thus, the magnitude of the force exerted by a raindrop on the Earth is $\text{2}\text{.4}\times {10}^{-5}\text{N}$ .