Electric Force 44Cde5
1. Problem 1: Given $L=0.50$ m, $q_1 q_2=8.0 \times 10^{-9}$ C, and angle $6^\circ$, find the distance and the electric force $F_E$.
2. Formula: Coulomb's law for electric force is $$F_E = k \frac{|q_1 q_2|}{r^2}$$ where $k=8.99 \times 10^9$ Nm$^2$/C$^2$.
3. Step 1: Find the distance $r$ using geometry or given data (not fully specified here, so assuming $r=L=0.50$ m).
4. Step 2: Calculate $F_E$:
$$F_E = 8.99 \times 10^9 \times \frac{8.0 \times 10^{-9}}{(0.50)^2} = 8.99 \times 10^9 \times \frac{8.0 \times 10^{-9}}{0.25} = 8.99 \times 10^9 \times 3.2 \times 10^{-8} = 287.68\, \text{N}$$
Final answer for problem 1:
- Distance $r = 0.50$ m
- Electric force $F_E = 288$ N (rounded)
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2. Problem 2: Given $q_1 = -30$ nC, $q_2 = +10$ nC, $r=0.020$ m, find $F_E$.
3. Step 1: Convert charges to Coulombs:
$$q_1 = -30 \times 10^{-9} = -3.0 \times 10^{-8} C$$
$$q_2 = 10 \times 10^{-9} = 1.0 \times 10^{-8} C$$
4. Step 2: Calculate $F_E$:
$$F_E = 8.99 \times 10^9 \times \frac{|(-3.0 \times 10^{-8})(1.0 \times 10^{-8})|}{(0.020)^2} = 8.99 \times 10^9 \times \frac{3.0 \times 10^{-16}}{0.0004} = 8.99 \times 10^9 \times 7.5 \times 10^{-13} = 6.74 \times 10^{-3} N$$
Final answer for problem 2:
- Electric force $F_E = 6.74 \times 10^{-3}$ N
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3. Problem 3: Given $q_1 - q_2 = +2e$ where $e=1.60 \times 10^{-19}$ C, $r=3.0 \times 10^{-10}$ m, $m_1 = m_2 = 6.64 \times 10^{-27}$ kg, find magnitude of $F_E$, magnitude of gravitational force $F_G$, and whether force is attractive or repulsive.
4. Step 1: Calculate $q_1 - q_2$:
$$q_1 - q_2 = 2 \times 1.60 \times 10^{-19} = 3.2 \times 10^{-19} C$$
5. Step 2: Calculate $F_E$:
$$F_E = 8.99 \times 10^9 \times \frac{(3.2 \times 10^{-19})^2}{(3.0 \times 10^{-10})^2} = 8.99 \times 10^9 \times \frac{1.024 \times 10^{-37}}{9 \times 10^{-20}} = 8.99 \times 10^9 \times 1.138 \times 10^{-18} = 1.02 \times 10^{-8} N$$
6. Step 3: Calculate gravitational force $F_G$:
$$F_G = G \frac{m_1 m_2}{r^2}$$ where $G=6.67 \times 10^{-11}$ Nm$^2$/kg$^2$.
$$F_G = 6.67 \times 10^{-11} \times \frac{(6.64 \times 10^{-27})^2}{(3.0 \times 10^{-10})^2} = 6.67 \times 10^{-11} \times \frac{4.41 \times 10^{-53}}{9 \times 10^{-20}} = 6.67 \times 10^{-11} \times 4.9 \times 10^{-34} = 3.27 \times 10^{-44} N$$
7. Step 4: Since $q_1 - q_2$ is positive, the force is repulsive.
Final answers for problem 3:
- $F_E = 1.02 \times 10^{-8}$ N
- $F_G = 3.27 \times 10^{-44}$ N
- Force is repulsive
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4. Problem 4: Given $q_1 - q_2 = -6.0 \times 10^{-6}$ C, $r=0.040$ m, $m_1=5.0 \times 10^{-6}$ kg, $m_2=2.5 \times 10^{-6}$ kg, find $F_E$, acceleration $a$ of particle A and B.
5. Step 1: Calculate $F_E$:
$$F_E = 8.99 \times 10^9 \times \frac{(6.0 \times 10^{-6})^2}{(0.040)^2} = 8.99 \times 10^9 \times \frac{3.6 \times 10^{-11}}{0.0016} = 8.99 \times 10^9 \times 2.25 \times 10^{-8} = 202.3 N$$
6. Step 2: Calculate acceleration $a$ of particle A:
$$a_A = \frac{F_E}{m_1} = \frac{202.3}{5.0 \times 10^{-6}} = 4.05 \times 10^7 \text{ m/s}^2$$
7. Step 3: Calculate acceleration $a$ of particle B:
$$a_B = \frac{F_E}{m_2} = \frac{202.3}{2.5 \times 10^{-6}} = 8.09 \times 10^7 \text{ m/s}^2$$
Final answers for problem 4:
- $F_E = 202.3$ N
- $a_A = 4.05 \times 10^7$ m/s$^2$
- $a_B = 8.09 \times 10^7$ m/s$^2$