Before thunder, the hair stands on end. A hair with a mass of 0.50 ng and a charge of 1.0 pC is supported by a force other than the weight of the hair and the electric force. What is the electric field strength?
Correct answer: A. 4.9 x 10^3 N C-1
- A. 4.9 x 10^3 N C-1
- B. 4.9 x 10^6 N C-1
- C. 4.9 x 10^5 N C-1
- D. 4.9 x 10^9 NC-1
Explanation
The electric force is equal to the weight.Electric force = Weight Eq = mgElectric field strength E = mg / q {mass should be in kg.)E = [(0.50 μg) × (9.8 m/s²)] / (1.0 pC)Now, let's plug in the values and convert units if needed:1 μg = 10^-9 kg1 pC = 10^-12 CE = [(0.50 × 10^-9 kg) × (9.8 m/s²)] / (1.0 × 10^-12 C)E = [4.9 × 10^-9 kg m/s²] / (1.0 × 10^-12 C)E = 4.9 × 10³ N/CSo, the electric field strength is 4.9 × 10³ N/C.
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