Momentum question. Acceleration on a moving track

In summary, the conversation discusses the concept of combining speeds of moving objects, specifically a train and a vehicle on top of it. The question is whether the speeds would be combined and if it is even possible. The experts explain that if the train is moving at 100 mph and the vehicle on it is also moving at 100 mph, their combined speed with respect to the ground would be 200 mph. However, this only applies if the vehicle is moving in the same direction as the train.
  • #1
Berts
3
0
Hi,

I've a question that is baffling me a little.

If a train was made so that it would act as a moving track / roadway and the cars were connected so as to complete a length of the track, in an oval for example. Say we accelerate the moving trackway to 100 Mph, and then a car accelerates to 100mph. Total speed = 200mph.

Now say you have a moving track on top of the railway track. Are all of the speeds combined, is it even possible? Would I imagine it would be like running on a travelator? So long as you joined the train at 100mph would you instantly accelerate to 200 mph?
It is hurting my brain and I know something in my thinking is incorrect!
 
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  • #2
Berts said:
So long as you joined the train at 100mph would you instantly accelerate to 200 mph?
How did that "instantly" come into this?
 
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Likes Berts
  • #3
A.T. said:
How did that "instantly" come into this?
Ah yes I see now,

But once on the train you could then accelerate the vehicle and go 200mph...
 
  • #4
Berts said:
Are all of the speeds combined, is it even possible?
I assume you mean something like this: Say a train is moving at 100 mph East with respect to the ground/track. And you, on the train, are riding a motorcycle at 100 mph East with respect to the train. (Pretend it's a long flat bed train.) Then your speed with respect to the ground will be 200 mph.

Is that what you mean?
 
  • #5
Doc Al said:
I assume you mean something like this: Say a train is moving at 100 mph East with respect to the ground/track. And you, on the train, are riding a motorcycle at 100 mph East with respect to the train. (Pretend it's a long flat bed train.) Then your speed with respect to the ground will be 200 mph.

Is that what you mean?
Yes thanks :-)
 

Related to Momentum question. Acceleration on a moving track

1. What is momentum?

Momentum is a measure of an object's motion, calculated by multiplying its mass by its velocity. It is a vector quantity, meaning it has both magnitude and direction.

2. How is momentum related to acceleration?

Momentum and acceleration are related through Newton's second law of motion, which states that the net force acting on an object is equal to its mass multiplied by its acceleration (F=ma). This means that a greater acceleration will result in a greater change in momentum.

3. How does momentum change on a moving track?

On a moving track, the momentum of an object can change due to changes in its velocity or mass. If the object's velocity increases, its momentum will also increase. If the object's mass increases, its momentum will also increase, and vice versa.

4. What is the difference between linear and angular momentum?

Linear momentum refers to the motion of an object in a straight line, while angular momentum refers to the motion of an object around a fixed point. Linear momentum is calculated by multiplying mass by linear velocity, while angular momentum is calculated by multiplying moment of inertia by angular velocity.

5. How does momentum affect collisions on a moving track?

In collisions on a moving track, the total momentum of the objects involved will remain constant, according to the law of conservation of momentum. This means that the sum of the momenta before the collision will be equal to the sum of the momenta after the collision.

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