Question

A scuba fiver dives directly from A to B, and then to C and then to the bottom of the sea at D she then realise that she has only 4 minutes' worth of oxygen left in her tank. She can ascend vertically at 10 cm/s AB=8cm, BC=12m and CD=16m. Can she reach the surface before her oxygen supply runs out?

Answer 1

The distance in centimeters

$\vert AB \vert= 8 cm, \vert BC \vert= 1200 cm,\vert CD \vert= 1600 cm$

$\vert AD \vert= \vert AB \vert+\vert BC \vert+\vert CD \vert= \\ =8+1200+1600= 2808 cm$

She can ascend vertically at 10 cm/s.

We will take the time ( T ) to get up:

$T= \frac{\vert AD \vert }{10}=\frac{2808}{10}=280.8 (s)$

$T= 280.8 s$

She has only 4 minutes' worth of oxygen left in her tank.

4 minutes = 4*60 =240 seconds

T> 4 minutes

Can she reach the surface before her oxygen supply runs out?

Answer:

A scuba fiver can't reach the surface before her oxygen supply ends.