Finding the acceleration of a crane trolley and it's load.

AI Thread Summary
The discussion focuses on calculating the acceleration of a crane trolley and its load, given a weight of 8526 N hanging at a 5.0° angle. The user seeks to understand the relationship between gravity and horizontal acceleration, noting that gravity does not directly affect horizontal motion unless friction is considered. A suggestion is made to utilize Newton's second law and draw a free body diagram to analyze the forces involved. It is emphasized that while the trolley moves horizontally, it may also be changing altitude, which requires work against gravity. Understanding these dynamics is crucial for solving the problem accurately.
Dylan.Wallett
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Homework Statement


An object of weight 8526 N hangs at an angle of 5.0° when the crane’s trolley at point P moves to the right with constant acceleration, as shown in the diagram.
Calculate the acceleration of the trolley and load.


Homework Equations


9.8 / tan (90-5) = 0.857 m/s^2


The Attempt at a Solution


I am looking for the intuition to the problem.
I have worked out that because there is no resistance in the equation so that the weight of the load does not effect horizontal acceleration only the work done to get the trolley up to acceleration magnitude.

I would like to know intuitively why gravity effects the horizontal acceleration of the trolley. I would appreciate your help.
 
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Welcome to PF!

Hi Dylan! Welcome to PF! :smile:

As is usual in dynamics questions, you only need to use good ol' Newton's second law F = ma

draw a free body diagram and take components in a convenient direction :wink:
 
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Likes Irfan Nafi
gravity does not affect horizontal acceleration (except through friction, which we are ignoring) but the acceleration is not completely horizontal. since the trolley is increasing its altitude (i assume, you do not indicate whether moving to the right is going up or down) some work must be done against gravity.
 
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