1. The problem statement, all variables and given/known data A 5.49 kg block covered in sandpaper is pushed along the ceiling of a room under construction. The block is pushed across the ceiling with a force of 81.6 N directed at an angle of 70.0° to the horizontal. If the coefficient of kinetic friction between the paper and the ceiling is 0.533, what acceleration does the block undergo? 2. Relevant equations component forces in x-direction = Fextcos70 - Ff 3. The attempt at a solution ma = Fextcos70 - uFn = 81.6cos70 - (0.533)(5.49*9.8) = 27.9 - 28.7 ** so i would get a negative number: that doesnt really make sense. Here I say that the normal force is equal in magnitude to the weight. Is this correct? Or do i need to include the y-component of the push when looking for the normal force? Help would greatly be appreciated!!