ΔK + ΔP = 0 ;
210 - 380 = - ΔP ;
ΔP = 170 ;
mgh = 170 ;
30 * 9.8 h = 170 ;
h = 0.578231 m <-------ans
A 30-kg girl is bouncing on a trampoline. During a certain interval after she leaves the...
A 40-kg girl is bouncing on a trampoline. During a certain interval after leaving the surface of the trampoline, her kinetic energy decreases to 220 J from 420 J. How high does she rise during this interval? Neglect air resistance
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