# Homework Help: Accelerating Wedge Problem, Help

1. Sep 16, 2008

### kky1638

Accelerating Wedge Problem, Help!!!

1. The problem statement, all variables and given/known data

A 45degree wedge is pushed along a table with constant acceleration A.
A block of mass m slides without friction on the wedge. Find its acceleration.
As always, find your result in an inertial frame.

2. Relevant equations

(x - X) = (h - y)cot (theta)

3. The attempt at a solution

I used the equation (x - X) = (h - y)cot (theta)
x = horizontal distance from the original place to the block
X = horizontal distance from the original place to the wedge
h = height of the wedge
y = vertical distance from the ground to the block

Since the angle is 45 degree, cot (theta) = 1 and
after differentiating twice gives, x.. - X.. = -y.. (.. means twice differentiated)

And X.. = A (the accel. of the wedge), so y.. = A - x..
And since y.. is not affected by A, isnt y.. just -g?

the answer clue in the book says "If A = 3g, y.. = g