A uniform board length L hinged about its lower end, held at θ above the horizontal is released from rest. As it passes through the horizontal what is the tangential acceleration of its outer tip? At first when I attempted this, I applied conservation of energy. (1/2)mv^2+mgh=(1/2)mv^2 + mgh but I did not get an answer. Then I decided could the answer just be L*gravity?? Any help given will be much apreciated! Thank you!