Frictionless Peg Slide On Wedge

AI Thread Summary
A user seeks help with a physics problem involving two blocks on inclined planes connected by a string, expressing anxiety about an upcoming exam. The problem requires calculating the acceleration of an 8kg block on a 40-degree slope and the tension in the rope connected to a 10kg block on a 50-degree slope. Respondents suggest starting with a diagram to visualize the forces acting on the blocks, particularly focusing on gravitational components along the slopes. They emphasize the importance of understanding vector calculations and breaking down forces into components. The user expresses gratitude for the assistance and acknowledges their stress about the exam.
LadyBlade
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Hey, I am new but was trying to find help online and found this site...hopefully someone will be willing to help me.

I used to be really good at mech but I've gone blank and my exams wed and i was wondering if someone could just help we with where to start even if they don't know the ans it would be helpful.

Q: a 8kg block is inclined on a 40 degree slope connected by a light string to a 10 kg block on a 50 degree slope which passes over a frictionless peg slide on a frictionless inclines. Find the acceleration of the 8kg block and the tension in the rope.


I really need help its a basics and I've forgot them and I am really panicing.

Sorry to bother you all

*LB*
 
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Do you remeber how to calculate vectors? (Gravity will pull straight down, so the angle of the inclines will give you the respective velocity vectors.)
 
Yes as he said. Simply draw a diagram of the 2 blocks (don't forget tension between the 2 blocks on the rope) for starters the force sliding the blocks down the plane is mgsin\theta

\theta = 50 degrees of course
 
Draw F = mg straight down. Use a right triangle to separate this F into a part along the slope and another component perpendicular to the slope.
 
Thank you thank you thank you...to you all! Thats really got me mad i really was drawing a blank...I'm pretty screwed if I am doing that 2 days before my 1st year exam at uni...whats year 2 and 3 ging to be like a dread to think! haha

Cheers All! :D
 
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