To find the difference in the diameters of Cell P and Cell Q, we first express both diameters in the same format.
Cell P: \[ 5.0 \times 10^{-4} , \text{m} \]
Cell Q: \[ 3.0 \times 10^{-5} , \text{m} \]
Next, we can convert Cell Q to the same exponent for easier subtraction. We can express \( 3.0 \times 10^{-5} , \text{m} \) as:
\[ 3.0 \times 10^{-5} = 0.3 \times 10^{-4} , \text{m} \]
Now we can subtract the two measurements: \[ \text{Difference} = \text{Diameter of Cell P} - \text{Diameter of Cell Q} \] \[ = 5.0 \times 10^{-4} , \text{m} - 0.3 \times 10^{-4} , \text{m} \] \[ = (5.0 - 0.3) \times 10^{-4} , \text{m} \] \[ = 4.7 \times 10^{-4} , \text{m} \]
Therefore, the difference in the diameters of the two cells is: \[ \boxed{4.7 \times 10^{-4} , \text{m}} \]