Which of the following is not a type of retarder?
Answers
Exhaust
Engine
Air
The correct answer and explanation is:
The correct answer is “Air”.
Explanation:
A retarder is a device used in vehicles, especially heavy-duty trucks and buses, to slow down the vehicle without relying solely on the regular braking system. Retarders help reduce wear on the traditional brakes and increase overall safety, particularly when descending steep grades or when the vehicle is carrying heavy loads.
There are three main types of retarders used in vehicles:
- Exhaust Retarder: This type of retarder uses the engine’s exhaust system to create resistance. It works by redirecting some exhaust gases into the engine cylinders, causing increased pressure that slows down the engine’s rotation. The energy used to slow the engine down is dissipated as heat, and this resistance helps to slow the vehicle. Exhaust retarders are commonly found on diesel-powered vehicles.
- Engine Retarder (or Jake Brake): The engine retarder, often known by the brand name “Jake Brake,” operates by altering the engine’s operation to create compression release in the engine. When the brake is applied, the exhaust valves are opened at the top of the compression stroke, releasing the compressed air. This reduces engine compression, which helps slow the vehicle. It is effective in maintaining vehicle speed on steep downhill gradients.
- Air Retarder: This is the term that is not typically used as a retarder in automotive systems. There are some systems that use air pressure to provide additional braking force, such as air brake systems, but they are not usually classified as “retarders.” In the context of retarders, the term “air” refers to the medium used in air brake systems (not a specific type of retarder). Therefore, “Air” is not considered a type of retarder in this context.
Retarders are a crucial part of modern heavy-duty vehicles, allowing for smoother and more controlled deceleration, especially when traveling down long slopes or with heavy cargo.