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acceleration on an angle

hi can anyone help with this maths question? I dont know where to start?
The mass of A is 4kg and the mass of B is 3kg inclined on a slope 30 degrees, body A will accelerate up the slope. if y (distance traveled up slope for A) =3m and x (distance hanging above floor for B ) find the velocity for which A hits the slope.

I know I will probably have to do it in two parts as the string goes slack but not sure where to start
Reply 1
https://ibb.co/Y7x8v79 here's a link to a photo of the question
Original post by panda34678
hi can anyone help with this maths question? I dont know where to start?
The mass of A is 4kg and the mass of B is 3kg inclined on a slope 30 degrees, body A will accelerate up the slope. if y (distance traveled up slope for A) =3m and x (distance hanging above floor for B ) find the velocity for which A hits the slope.

I know I will probably have to do it in two parts as the string goes slack but not sure where to start

The usual starting point for questions like this is to annotate the diagram with the forces acting on both masses. Then you can put together equations of motion (based on Newton's second law, F = ma) separately for the two masses, and from that you can find the acceleration of the masses.
Reply 3
I found the acceleration of B to be 9.8m/s and A to be 4.9m/s but shouldn't they be the same? I then found the velocity of A to be 7.4m/s for 2.8m but can't seem to work out how to figure out how it travels for the last 0.2 m. I know it is decelerating but that's all ive got
Original post by panda34678
I found the acceleration of B to be 9.8m/s and A to be 4.9m/s but shouldn't they be the same? I then found the velocity of A to be 7.4m/s for 2.8m but can't seem to work out how to figure out how it travels for the last 0.2 m. I know it is decelerating but that's all ive got

I think you may have overlooked string tension in your consideration of forces. For example, Mass B has the force 3g acting vertically downwards and the string tension T acting vertically upwards. The value of T is unknown, but you can eliminate T from the pair of equations of motion by solving them simultaneously.
Reply 5
ah thank you I will try that

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