Let's solve part (a) as an example, step by step: --- ## Part (a): ### Step 1: **Identify Current Directions and Arrangement** - There are three wires. - The top wire has current **out of the page** (denoted by a dot). - The bottom two wires have current **into the page** (denoted by a cross). **Explanation:** The direction of the force between two parallel currents depends on their directions: - **Same direction:** They attract. - **Opposite direction:** They repel. --- ### Step 2: **Determine Net Magnetic Force on Each Wire** #### **Top wire (+)** - It feels a **repulsive force** from each of the bottom wires (since their currents are opposite). - The repulsive forces it **down and diagonally outward** from each lower wire. - The net force is **straight down** (y-direction), since the two lower wires are symmetric about the vertical axis. #### **Bottom left wire (-)** - It feels a **repulsive force** from the top wire (upward and to the left). - It feels an **attractive force** from the other bottom wire (to the right). - The net force is **upward and to the right**. #### **Bottom right wire (-)** - Similar reasoning as the bottom left wire, but in the opposite direction. - Repulsive from top wire (upward and to the right), attractive from other (-) wire (to the left). - The net force is **upward and to the left**. **Explanation:** For each wire, sum the vector forces from the other two, using the rule above. --- ### **Final Answer for (a):** - **Top wire (+):** Net force is **downward**. - **Bottom left wire (-):** Net force is **upward and right**. - **Bottom right wire (-):** Net force is **upward and left**. --- Let me know if you want a step-by-step for the other parts (b, c, d) as well!