A positively charged oil drop is injected into a region of uniform electric field between two oppositely charged, horizontally oriented plates spaced $16 \mathrm{cm}$ apart. If the electric force on the drop is found to be $9.6 \times 10^{-16} \mathrm{N}\( and the potential difference between the plates is \)480 \mathrm{V}$ what is the magnitude of the charge on the drop in terms of the elementary charge \(e\) ? Ignore the small buoyant force on the drop.

Short Answer

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#tag_title#Step 2: Calculate the electric field#tag_content# Now, we can plug the values into the formula and calculate the electric field: $$ E = \frac{480 \mathrm{V}}{0.16 \mathrm{m}} = 3000 \frac{\mathrm{V}}{\mathrm{m}} $$ The electric field between the plates is 3000 V/m. #tag_title#Step 3: Calculate the charge on the oil drop#tag_content# We can use the formula for electric force: $$ F = Eq $$ Where F is the electric force acting on the charge, E is the electric field, and q is the charge. We are given F = 2.5 x 10^(-15) N and E = 3000 V/m. We need to find the charge, q, so we can rearrange the formula to solve for q: $$ q = \frac{F}{E} $$ Now, plug in the values: $$ q = \frac{2.5 \times 10^{-15} \mathrm{N}}{3000 \frac{\mathrm{V}}{\mathrm{m}}} $$ #tag_title#Step 4: Calculate the charge in terms of elementary charge#tag_content# Now, we can calculate the value of q: $$ q = \frac{2.5 \times 10^{-15} \mathrm{N}}{3000 \frac{\mathrm{V}}{\mathrm{m}}} = 8.33 \times 10^{-19} \mathrm{C} $$ To express the charge in terms of elementary charge (e = 1.6 x 10^(-19) C), we can divide the charge, q, by the elementary charge: $$ \frac{8.33 \times 10^{-19} \mathrm{C}}{1.6 \times 10^{-19} \mathrm{C}} = 5.2 $$ This means the charge on the oil drop is approximately 5.2 times the elementary charge.

Step by step solution

01

Determine the electric field between the plates

We can use the formula for electric field between the plates of a parallel-plate capacitor: $$ E = \frac{V}{d} $$ where E is the electric field, V is the potential difference between the plates, and d is the distance between the plates. We are given V = 480V and d = 16cm = 0.16m. So, we can calculate the electric field as follows: $$ E = \frac{480 \mathrm{V}}{0.16 \mathrm{m}} $$

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