Answer:
7800kg/m³
Explanation:
Density of iron in CGS unit is 7.8 g/cm3. Its density is SI is
Given the density of iron = 7.8 g/cm3.
The SI units must be in kg/m³
7.8g = 7.8/1000 kg
7.8g = 0.0078kg
1cm³ = 0.000001m³
7.8g/cm³
= 0.0078/0.000001 kg/m³
= 7800kg/m³
Hence the density in SI unit is 7800kg/m³
A=mgh
m=300g=0.3kg
g=9,81 m/s^2
h=10m
A=29.43J