Trying to give myself a solid study guide--please show all work/steps so I can e
ID: 1972133 • Letter: T
Question
Trying to give myself a solid study guide--please show all work/steps so I can easily follow your process. Thank you so much!
Jason Bourne is trapped on a fast-moving train moving at 30.0 m/s, making jumping off the train out of the question,
even for Bourne. However, he has planned a clever escape. He has planted some C4 explosive on the hinge linking
the caboose (the final car of the train) to the remainder of the train. His intention is to move into the caboose and
then detonate the explosive, thereby bringing the caboose car to rest. He can then step off the caboose and walk to
safety, while the rest of the train speeds away (at a slightly increased speed). There are a total of 31 cars in the train,
including the caboose. Each car has a mass of 1000.0 kg.
What is the change in the kinetic energy of the system (the caboose, and the rest of the train) as a result of the
explosion, and how much C4 explosive should Bourne plant on the hinge (The explosive C4 releases about 3860 Joules per gram. Assume that all of this energy is converted into kinetic
energy of the train cars)?
(I realize that ^ there are sort of two parts to this, but being as they build on one another I didn't think it wise to try and separate them?)
Explanation / Answer
This problems involves conservation of Kinetic Energy. Key words "all energy is converted to KE" aka no energy is lost. KE of caboose = 1/2mv^2 Change in KE_caboose = KEf - KEi = 0 - 1/2mv^2 = -1/2mv^2 Change in KE_rest of train = -(Change in KE_caboose) Change of KE of system = change KE_caboose + change KE_rest of train = 0 KE_caboose = 1/2mv^2 = 1/2(1000kg)(30m/s)^2 Which is also equal to the amount of energy needed to stop it since we want vf to be 0m/s. Therefore: (Grams of C4) = (KE_caboose)/(3860 J/g) Please rate!
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.