posted by James .
A bullet is fired through a board 12.1 cm thick, with a line of motion perpendicular to the face of the board. If the bullet enters with a speed of 375 m/s and emerges with a speed of 205 m/s, what is its acceleration as it passes through the board? (Take the direction the bullet is moving to be the positive.)
Vf^2=Vi^2+2ad solve for a