When a golf ball is lowered into a measuring cylinder containing water, the water level rises by 30 cm3 when the ball is completely submerged. If the mass of ball in air is $33\ g$, find its density.

Here given, the mass of the ball $m=33\ g$

Rise in the water level when the ball is completely submerged $V=30\ cm^3$

Therefore, density $=\frac{mass(m)}{volume(V)}$

$=\frac{33\ g}{30\ cm^3}$

$=1.1\ g/cm^3$

Therefore, the density of the golf ball is $1.1\ g/cm^3$.