Frictionless Peg Slide On Wedge

[LadyBlade]

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*

 

[LURCH]

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.)

 

[djeitnstine]

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

 

[Delphi51]

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.

 

[LadyBlade]

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