Hi Jackie,
To figure out how many Jupiters would fit inside the
Sun, we just need to compare the volumes of Jupiter and the Sun. If we
assume that both Jupiter and the Sun are spherical, then their volumes can
be determined from V=(4x pi x R^3)/3. The radius of the Sun is about
R=695,000 km, so the volume of the Sun is about V=1.4x10^18 km^3. I
wrote this down in scientific notation (the x10^18 part) because it is
kind of a pain to type 1,400,000,000,000,000,000 (I hope I counted my
zeroes correctly!). The radius of Jupiter is about R=69,911 km, so Jupiter's volume is about 1.4x10^15 km^3. If we divide the volume of the
Sun by the volume of Jupiter, we get about 1x10^3, which means that 1,000 Jupiters would fit inside the Sun.
Kris