When towing bulky items from one place to the other, the only thing that many people want to make sure is that they can haul as much luggage as possible without violating the local traffic rules and regulations. However, following the rules does not always mean your load and truck are safe on the road. One of the main reasons why towing accidents occur is poor load distribution which ruins the stability of the vehicle. This leads to whipping, especially when the speed picks up and eventually, it could cause rolling. Understanding the physics behind vehicle load distribution and motion can help you avoid these complications.

The centre of gravity of the vehicle

The centre of gravity is sometimes abbreviated as the CG of a vehicle. It is the single point where the weight of the entire object is considered to act. It is like a 3D balance point for the car, and it is where all forces of acceleration acting on the object pass through. Ideally, the centre of gravity of a vehicle should be as low as possible to reduce the possibility of external forces from acting on it and tipping it, leading to rolling. 

How towing affects the vehicle's centre of gravity

There is a general rule which states that the tow ball weight should be about 10 per cent of the entire vehicle's weight. This is the maximum amount of weight that can be towed without changing the vehicle's centre of mass. When the load gets heavy, the CG shifts and controlling the vehicle will not be as simple as when the vehicle is not loaded. The challenge becomes even stiffer when the driver has to navigate sharp bends and turns, and if not well managed, rolling can result.

Forces which act on the tow truck when negotiating a bend

When your tow truck is travelling in a straight line, only its momentum is working on it. When you reach a curve and turn the wheels, a centrifugal force resists the circular motion, trying to push the truck outwards. The tires have to counter the centrifugal force, and their effectiveness depends on the load the vehicle is carrying and its speed. If the speed is too high, the truck will run off the road and roll.

The key to the reduction of towing accidents, especially on corners is carrying the right weight and avoiding over speeding. This keeps the motion of the car and the forces acting on it manageable for you behind the steering wheel, helping you keep the truck on the road.

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