Final answer:
A self-energized brake shoe will tend to apply greater force due to its mechanism that takes advantage of the motion of the vehicle to increase braking force. Friction in this context creates heat, which can cause brakes to overheat if used excessively.
Step-by-step explanation:
When a brake shoe is "self-energized," that shoe will have a tendency to apply greater force. This means that a self-energization mechanism uses the motion of the vehicle to increase the braking force applied. As a result, less effort is required from the braking system to slow down or stop the vehicle. The self-energizing action occurs because, under certain conditions, the rotation of the drum can drag the shoe into tighter contact, thereby applying a greater force on the drum and increasing the braking effect.
In the context of thermal energy and friction, the motion of a vehicle is converted into heat energy through the friction between the brake pads and rotors. This principle is similar to when you clap your hands, and the friction produces heat, warming your palms. The friction in the brake system is deliberate and crucial for slowing down or stopping the vehicle. This process can also lead to the overheating of brakes, especially if they are used excessively, such as when descending long mountain roads.