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A rubber band begins exerting a tension force when its length is 8 cm. As it is stretched to a length of 10 cm its tension increases with length, more or less steadily, until at the 10 cm length the tension is 3 Newtons. *
Between the 8 cm and 10 cm length, what are the minimum and maximum tensions?
answer/question/discussion:
max tension= 3N minimum tension= 0N
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Assuming that the tension in the rubber band is 100% conservative (which is not actually the case) what is its elastic potential energy at the 10 cm length?
answer/question/discussion:
3N * 0.1m= 0.3Joules assuming 100% conservation
@& Right idea, but the energy is determined by the average force, not the maximum force.
What is the average tension, and what therefore is the elastic potential energy, based on the average tension?*@
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If all this potential energy is transferred to the kinetic energy of an initially stationary 20 gram domino, what will be the velocity of the domino?
answer/question/discussion:
0.02kg*9.8m/s^2= -0.196N + 3N= 2.8N Net force 2.8N= 0.02kg * a
a= 140m/s^2 v0= 0m/s
This is about as far as I can get at the moment.
@& KE = 1/2 m v^2.
If all the PE gets converted to KE, what therefore will be the velocity v?*@
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If instead the rubber band is used to 'shoot' the domino straight upward, then how high will it rise?
answer/question/discussion:
Once I find the values for the previous question I can calculate this.
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" "20 minutes" ""
@& Don't spend more that about 15 minutes on this before sending it to me, with your best thinking. My guess is that you will solve it in that time, but if not I'll give you more hints.*@