Rotational motion of rear wheels

AI Thread Summary
The discussion focuses on calculating the weight supported by the rear wheels of a car when its front wheels are elevated. When the front of the car is raised, the center of gravity shifts, causing more weight to be distributed to the rear wheels. Participants emphasize the importance of using a free-body diagram to visualize the forces acting on the car, including the normal forces at each wheel set. There is confusion regarding the horizontal surface forces and how to set up the problem. Understanding the distribution of weight and the role of the center of mass is crucial for solving the problem effectively.
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A 1500 kg car is driven onto a pair of ramps so that it fronts wheels have been raised 0.3 m above the rear wheels. The wheel base of the car is 2.4m and it center of gravity is located at the midpoint between the front and rear wheels. How much of the car's weight is supported by the rear wheels? - The problem I'm having in this question is interpreting what the question is asking for. I just need on on setting up the problem as on what I should find first. Thanks

This is what I drew but I have no idea what to use to solve with these given information.
2Oo2Bn4.jpg
 
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When the car is level, it's weight is distributed evenly between the front and rear wheels, but when the front is lifted higher, more weight gets pushed onto the back than the front. Can you see why?

What has happened to the weight vector, compared with the wheel positions, to make that happen?

If you draw a free-body diagram of the situation - you get two normal forces: one from the front wheels and one from the back wheels. You also get horizontal surface forces at each wheel-set.
 
@Simon, thank you for the reply.
For the first question, yes I can see why the weight would be pushed back. For the second question, I don't know what that really mean. I understand why there is two normal force because of the wheel set but I do not understand the horizontal surface forces part. What would I have to find first in this case? Thanks again.
 
The question involves a free body diagram where not all the forces act through the center of mass.
Other than that, it is still statics.
 
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