Calculating Acceleration and Tension in a Rope and Pulley System

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AI Thread Summary
The discussion centers on calculating the acceleration of a motorcycle and the tension in a rope within a pulley system, with a focus on a 950kg mass. Participants express confusion about the role of the ramp and the relevance of a 10-degree angle, which was mistakenly referenced from another problem. The net force acting on the system is identified as equal to the gravitational force on the mass, leading to the need to divide this force by the total system mass to find acceleration. Emphasis is placed on treating the motorcycle and the weight as separate systems while ensuring consistent variable naming and direction for accelerations. The conversation highlights the importance of clear problem parameters and the correct application of physics equations.
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Homework Statement


An environmentally-sensitive daredevil wants to use a large mass, a rope, and a pulley to accelerate toward ramp while his motorcycle is in neutral, as shown below. If friction is negligible, what will the acceleration of the motorcycle be and the tension of the rope?

TvEAo.jpg


Homework Equations



guy: Ft = ma

weight: Ft - mg = ma

I think...

The Attempt at a Solution



I don't know how to get acceleration because I don't know Ft...
 
Last edited:
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Does the question want you to calculate his accelerate on the ramp, or before it? Either way, you can't calculate tension right off the bat. The net force is going to equal the force of gravity on the 950kg mass. Divide that force by the system mass and you should get the acceleration before the ramp.
 
fLambda said:
Does the question want you to calculate his accelerate on the ramp, or before it? Either way, you can't calculate tension right off the bat. The net force is going to equal the force of gravity on the 950kg mass. Divide that force by the system mass and you should get the acceleration before the ramp.

I'm not sure, it just asks for acceleration, I still need help with this question.
 
Where does the 10 degrees come from? I don't see that in the question. If it's the slope of the ramp, that's not relevant. The question only asks you to consider circumstances before the ramp is reached, and nothing else is touching the ramp. The string is either horizontal or vertical.
The most obvious way to approach the question (not necessarily the most elegant) is to consider the weight and the motorcycle-with-rider as two separate systems but with certain parameters in common. Each has a set of forces and an acceleration. Which of these do they share? Can you write down the free body equation for each?
 
haruspex said:
Where does the 10 degrees come from? I don't see that in the question. If it's the slope of the ramp, that's not relevant. The question only asks you to consider circumstances before the ramp is reached, and nothing else is touching the ramp. The string is either horizontal or vertical.
The most obvious way to approach the question (not necessarily the most elegant) is to consider the weight and the motorcycle-with-rider as two separate systems but with certain parameters in common. Each has a set of forces and an acceleration. Which of these do they share? Can you write down the free body equation for each?

Sorry! The 10 degrees came from a different question, I looked off the wrong question, I've fixed it now.
 
PhysicsNoob76 said:
guy: Ft = ma
weight: Ft - mg = ma
Using the same m for both masses is going to be confusing. Use a different name for each different variable.
Also, make sure you're measuring accelerations all in the same direction.
 

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