A 1.50 kg snowball is fired from a cliff 13.5 m high with an initial velocity of 14.0 m/s, directed 41.0° above the horizontal. (a) Using energy techniques, rather than techniques of Chapter 4, find the speed of the snowball as it reaches the ground below the cliff. ok so I used the equation k1+u1=k2=u2 plugging in numbers i did 1/2(1.50kg)(14m/s)^2+(1.50kg)(9.8m/s^2)(13.5m)=1/2(1.50kg)(vf)^2+(1.50kg)(9.8m/s)(0). Then I solve for Vf and I get a wrong answer. Now i realize this is probably wrong since I haven't incorporated the angle, but I'm not sure. Any ideas?