Question

A swimming pool is 1.4 m deep and 12 m long. Is it possible for you to dive to the very bottom of the pool so people standing on the deck at the end of the pool do not see you?

Answer 1

Answer:

$r = 1.59 m$

So this is smaller than the length of the swimming pool and hence we can say that diver will not be visible to the person sitting at deck

Explanation:

If the diver is at the bottom of the swimming pool then we will say that the nobody on the deck will able to see if light coming from the diver will have total internal reflection

so we will have

$n_1 sin\theta_1 = n_2 sin\theta_2$

here we will have

$n_1 = \frac{4}{3}$ for water

$n_2 = 1$

$\theta_2 = 90$

now we have

$\frac{4}{3}sin\theta_1 = 1$

now we have

$\theta_1 = 48.6$

now let say the radial distance from the position of diver is"r"

so we have

$tan\theta = \frac{r}{h}$

$tan48.6 = \frac{r}{1.4}$

$r = 1.59 m$

So this is smaller than the length of the swimming pool and hence we can say that diver will not be visible to the person sitting at deck