First the crew was to inspect and survey the lunar surface. This included investigating surface features and obtaining material samples from the selected Hadley-Appennius area of the Moon. The next mission goal was to set-up surface experiments. Next the crew was to evaluate the capability of the Apollo equipment to provide extended lunar surface stay time.
The final objective was to conduct inflight experiments and complete photographic tasks from lunar orbit. The entire mission lasted 12 days from initial launch to splash down.
Like all other Apollo missions the crew consisted of three astronauts. The mission commander was David R. Scott who was completing his third space flight. The command module pilot and lunar module pilot were Alfred M. Worden and James B. For both pilots it was their only space flight. Like all lunar missions, one of the pilots remained while the lunar module pilot and the commander went to the surface to complete the surface portion of the mission. Apollo 15 was the first mission to use the lunar roving vehicle.
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Connect and share knowledge within a single location that is structured and easy to search. I think that a car which is applying its max force on Earth stops accelerating as in, stops increasing in speed because of air resistance.
But on the moon there is none so I think the car would accelerate indefinitely. The curve of the moon is very slight, but at some great speed would the car ever lift off the ground and fly into space? The major friction encountered by a vehicle on the moon will be rolling friction. The surface of the moon is covered in a fine "dust" that is deformed by the pressure of the tires of the vehicle and more so by boots :. This means that the wheel is always "rolling up hill" against weak moon gravity; that is experienced as rolling friction because work has to be done to move forward.
You experience this when driving a car along the beach - you need to be in low gear and fuel consumption shoots up.
Aside from this, if your lunar vehicle was powerful enough to overcome the friction and somehow kept accelerating, the uneven surface of the moon would keep it from maintaining contact with the moon surface - it would spend a lot of time "suspended" with the wheels spinning.
Assume that you made a completely smooth, straight "runway" - overcoming the above objections - you would accelerate until you reached the velocity of the "low" orbit of the moon - in other words, you would lift off when you were driving at the speed at which a satellite would orbit.
At that moment your normal force would be zero and wheels no longer work. But you would not reach escape speed by doing that.
See for example the second block on this page. Assume that you have a conventional automobile, but with a very very powerful engine- that can continue to produce enough power to accelerate even when it is travelling at a very high velocity and with huge frictional losses and air resistance.
Now that we got the weakness of the engine out of the way, let us assume that there is a perfectly 'smooth' and 'straight' road constructed all the way around the moon. By smooth, I mean smooth as a racetrack and not smooth like a skating rink, ie. It does not have any macroscopic bumps, etc. Having defined the operating conditions which, I hope, is what the OP asked , let us examine how the car accelerates.
The engine exerts a torque on the wheels, which is translated to motion if there is sufficient friction between the wheel and the road. As we all know, the limiting friction that the road can exert on the car, accelerating it depends on the amount of normal or contact force between the road and the wheels of the car.
If the normal force is large, a large amount of friction is available and the car, if it has a powerful enough engine, can accelerate by a large amount. However, if the normal force becomes zero, there can be no frictional force. The normal force is provided by the force of gravity on your car. Let us make an assumption about our car. Let us assume that it has good aerodynamics for speeding, ie. When we start to zoom around the moon in our hypothetical car, initially, we will accelerate normally as normal as you can expect in the moon.
Granted, the maximum acceleration will be much lower than the acceleration you can expect on Earth, but still you can accelerate. However, as you keep increasing your speed, something strange happens. You will find that the maximum acceleration you can maintain without skidding on the road keeps reducing. This is because, as you keep increasing your speed, the centrifugal force due to your motion around the moon starts coming into picture, and it acts against the gravitational force, effectively reducing the amount of normal force on the tyres of the car, lowering your acceleration.
This will continue, until you slowly reach the orbital speed on the surface of the moon, where the gravitational force is completely balanced by the centrifugal force due to your motion. At this point, your car engine becomes useless even if it has plenty of spare power , as your car is effectively floating around now.
Thus, the orbital speed of the moon is the largest speed that you can achieve when travelling in a conventional automobile, although there are plenty of easier ways to travel at this speed. Nothing with mass can accelerate indefinitely. What it seems you are asking is about coasting. While its true that there is a degree of energy loss from wind resistance, there is also a great deal in the axles of your vehicle.
You would decelerate on a flat track more slowly, but you would eventually lose all of your kinetic energy. To answer your second question, you need to remember that the moon is not a ping pong ball. While it is much smaller than Earth, it still has a sufficient amount of mass that the mass of you or a car is utterly insignificant to it, so you can't just escape with the engine available in your average production car.
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