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A 30kg child moving at 4m/s jump onto a 50kg sled that is initially at rest on a long frictionless,horizontal.
a) find the speed after the child jumps onto the sled
b)find Kinetic Energy of the child after the child jumps onto the sled
After coasting at constant speed for a short time, the child jumps off the sled in such away that she is at rest with respect to the ice
c) find the speed of the sled after the child jumps off
d) find the kinetic energy of the child-sled system when the child is at rest on the ice
e)Compare the Kinetic energy that were determined in part b and d . If the energy greater in d that b, where did the increase come from? . If the energy is less in d than b , where did the energy go.
a)30*4+50*0=v(30+50)
v=1.5
b)1/2(30+50) *1.5^2
KE=90
c)1.5(80)=1.5(30)+50v
v=1.5
d)0
e) d have less energy than b, the energy transform to heat
a) find the speed after the child jumps onto the sled
b)find Kinetic Energy of the child after the child jumps onto the sled
After coasting at constant speed for a short time, the child jumps off the sled in such away that she is at rest with respect to the ice
c) find the speed of the sled after the child jumps off
d) find the kinetic energy of the child-sled system when the child is at rest on the ice
e)Compare the Kinetic energy that were determined in part b and d . If the energy greater in d that b, where did the increase come from? . If the energy is less in d than b , where did the energy go.
a)30*4+50*0=v(30+50)
v=1.5
b)1/2(30+50) *1.5^2
KE=90
c)1.5(80)=1.5(30)+50v
v=1.5
d)0
e) d have less energy than b, the energy transform to heat