The surface density of luminous matter in a galaxy has units of mass per area and obeys the equation

\[D(r) = D_0 e^{-r/r_0},\]

where \(D_0\) is some constant with units of mass per area. Suppose we have some galaxy where \(D_0 = 0.25 \text{ kg}/\text{m}\). What is \(D(2r_0)\) in units of \( \text{ kg}/\text{m}\), to the nearest thousandth?

×

Problem Loading...

Note Loading...

Set Loading...