Grade 11 electricity examples

📚 Quick Study Guide

• ⚡️ Electric Charge: Measured in Coulombs (C). Elementary charge, $e = 1.6 \times 10^{-19}$ C.
• 💡 Coulomb's Law: Describes the electrostatic force between two charges: $F = k \frac{|q_1q_2|}{r^2}$, where $k = 8.99 \times 10^9 Nm^2/C^2$.
• 🔌 Electric Field: Force per unit charge: $E = \frac{F}{q}$. For a point charge: $E = k \frac{q}{r^2}$.
• 🔋 Electric Potential: Potential energy per unit charge: $V = \frac{U}{q}$. Potential difference (voltage) between two points: $\Delta V = - \int E \cdot dl$.
• 🌊 Current: Rate of flow of charge: $I = \frac{\Delta Q}{\Delta t}$, measured in Amperes (A).
• 🚧 Resistance: Opposition to current flow: $R = \frac{V}{I}$, measured in Ohms ($\Omega$).
• 🔥 Ohm's Law: $V = IR$.
• 🧮 Power: Rate at which energy is transferred: $P = VI = I^2R = \frac{V^2}{R}$, measured in Watts (W).
• 🤝 Series Circuits: Components are connected end-to-end. Total resistance: $R_{total} = R_1 + R_2 + ...$. Current is the same through all components.
• 🧱 Parallel Circuits: Components are connected side-by-side. Total resistance: $\frac{1}{R_{total}} = \frac{1}{R_1} + \frac{1}{R_2} + ...$. Voltage is the same across all components.

🧪 Practice Quiz

1. What is the magnitude of the electrostatic force between two charges of +2 μC and -3 μC separated by a distance of 2 cm?
   1. 45 N
   2. 135 N
   3. 90 N
2. A 12V battery is connected to a resistor. If the current flowing through the resistor is 2A, what is the resistance of the resistor?
   1. 6 $\Omega$
   2. 24 $\Omega$
   3. 4 $\Omega$
3. What is the electric field strength at a distance of 0.5 m from a point charge of 5 nC?
   1. 90 N/C
   2. 180 N/C
   3. 45 N/C
4. Two resistors, 10 $\Omega$ and 20 $\Omega$, are connected in series to a 9V battery. What is the current flowing through the circuit?
   1. 0.3 A
   2. 0.45 A
   3. 0.9 A
5. Two resistors, 10 $\Omega$ and 20 $\Omega$, are connected in parallel to a 9V battery. What is the total current supplied by the battery?
   1. 1.35 A
   2. 0.45 A
   3. 0.9 A
6. A light bulb is rated at 60W and operates at 120V. What is the current flowing through the light bulb?
   1. 0.5 A
   2. 2 A
   3. 1.5 A
7. What is the electric potential energy of a -4 μC charge at a point where the electric potential is 500 V?
   1. -2 mJ
   2. 2 mJ
   3. -0.2 mJ