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[Mikkelc2323]

So basically I signed up here just to get an answer on this question.

 

Lets say we have a car, with a caravan attached to it. We have the choice to put a block of 500 kilograms in either the car or the caravan. It has to be placed in one of those. There's about 1 meter between the back of the car, and the start of the caravan.

 

Is there any difference on the amount of resistance on the cars energy depending of what choice we picked and why?

 

I hope you understand my question, else I will happily explain further.

[Mordred]

mass is "resistance to inertia change" So placement does matter. The added mass will affect turning radius as a change in direction is a change in inertia. So is accelerating and deceleration.

 

This is a Newtons three laws of inertia type question. Obviously you don't want to place the mass too high.

Edited July 10, 2016 by Mordred

[Mikkelc2323]

So it would be better to place the block in the car, or just as close as possibly to the car?

 

Also thanks for the quick answer.

[Mordred]

So it would be better to place the block in the car, or just as close as possibly to the car?

 

Also thanks for the quick answer.

You want you added weight as low to the ground as possible and with a vehilcle trailer situation. Ideally on the vehicle. (less swing). Otherwise on the trailer between the front tire and the vehicle. As close to the hitch as possible. The added weight will also help keep the hitch in place.

 

Placement as far forward on the trailer is extremely important. Particularly if you need to skid sideways to a halt.

 

Though you also want to make sure you don't have too much weight forward of the front tire of the trailer. As you may place too much downward stress on the hitch. If thats the case then place the heavier portion directly above the axle. You will induce more fishtail swing. However less stress on the hitch.

 

In all cases keep your load balanced between the left and right hand side of the trailer

Edited July 10, 2016 by Mordred

[Sensei]

You should check manual of your caravan what is maximum weight it can stand, and where it should be placed. It should be described in manual. Alternatively you can search the net for model name you have.

If it cannot stand 500 kg (with all the other stuff you have in it), there is no question were to put it.. or you will destroy caravan.

Subtract MTPLM (Maximum Technically Permissible Laden Mass) from Unladen Weight.

f.e. this model

http://www.venture-caravans.com/new-adria-adora-612-dt-rhine-current-6berth-northamptonshire-ck0190c76

has 1700 kg-1503 kg=197 kg

I checked maybe 10 models in above library, and none from 1st page had higher than 200 kg max load.

 

Heavy weight should be placed near axis.

 

Additionally driving speed should be adjusted to weight you have in car and caravan.

 

ps. Mods should adjust thread title accordingly..

Edited July 10, 2016 by Sensei

[Mordred]

good point Sensei on checking vehilcle owners manual.+1

Edited July 10, 2016 by Mordred

[Mikkelc2323]

Im going to simplify my question, sorry you do not seem to understand it: (500 kg was just an example, it could be 50 kg)

 

Lets say the car goes 50 mph with the caravan on, and we have to keep that speed. We then add those extra kilograms. Would the car use more power to go 50 mph if the weight was placed in the caravan, as the weight would be longer away from the car, or would it be exactly the same if the weight was placed IN the car.

 

Sorry for being unclear!

[Mordred]

as far as strictly mass vs momentum. Your still moving the same amount of mass. So wont change fuel efficiency by placement.