The density of iron is 7.8 x 10³ kg m^-3. What is it's relative density ?

We know,

R.D. = $\dfrac{\text {Density of substance in kg m}^{-3}}{\text{1000 kg m}^{-3}}$

Given,

density of iron = 7.8 x 10³ kg m^-3

Substituting the values in the formula above we get,

R.D. = $\dfrac{7.8 \times 1000 \text { kg m}^{-3}}{\text{1000 kg m}^{-3}}$

Therefore,

Relative Density of iron = 7.8