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GingerBread27
Oct13-04, 01:53 PM
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?

Galileo
Oct13-04, 02:22 PM
Well. The technique is right, so you must've made some silly error in solving for Vf.
What answer did you get? It should be 21.5 m/s.

GingerBread27
Oct13-04, 02:43 PM
Yeah 21.5 is the answer, guess I must have made a mistake with the calculator :blushing: . Thank You :smile:

HobieDude16
Oct13-04, 07:58 PM
Hey GingerBread27 please check your private messages...thanks!

HobieDude16
Oct13-04, 08:09 PM
GingerBread27 check your private messages 1 more time...thanks