Insights Blog
-- Browse All Articles --
Physics Articles
Physics Tutorials
Physics Guides
Physics FAQ
Math Articles
Math Tutorials
Math Guides
Math FAQ
Education Articles
Education Guides
Bio/Chem Articles
Technology Guides
Computer Science Tutorials
Forums
Intro Physics Homework Help
Advanced Physics Homework Help
Precalculus Homework Help
Calculus Homework Help
Bio/Chem Homework Help
Engineering Homework Help
Trending
Featured Threads
Log in
Register
What's new
Search
Search
Search titles only
By:
Intro Physics Homework Help
Advanced Physics Homework Help
Precalculus Homework Help
Calculus Homework Help
Bio/Chem Homework Help
Engineering Homework Help
Menu
Log in
Register
Navigation
More options
Contact us
Close Menu
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Forums
Homework Help
Introductory Physics Homework Help
Conservation of Momentum- Inelastic Collisions
Reply to thread
Message
[QUOTE="Crusader711, post: 4556143, member: 492637"] [b]1. This was a hard test question that I took partial credit on. I want to fully understand what I did wrong so that I’m fluid with the concept. I’m also new to this forum. I love constructive criticism too! lol Zombie Apocalypse has arrived and the war has begun. Your task as a physics student is to gather intel on the Kinetic energy lost due to the collision of darts on their vulnerable heads. Your crossbow can be modeled as a spring with a 1500N/m constant that can be drawn back to a 32cm maximum. You shoot your 35.0 gram crossbow dart at the zombie's 5.1kg head, striking it horizontally level as fired from your position. The dart buries itself in the zombie's head, and the head slides back across the level table. The CIA needs the fractional amount of Kinetic energy lost in the collision compared to the initial kinetic energy, that is, [delta KE]/KEi [/b] [b]2. Homework Equations : Crossbow Dart KE= 1/2kx^2 Conservation of Momentum Before Collision- Pi= m1v1 + m2v2= kg/m/s KEi= 1/2m1v1^2 + 1/2m2v2^2= Joules After Collision- P’= m1v1’ + m2v2’= kg/m/s KEf= 1/2m1v1^2’ + 1/2m2v2^2’= Joules …m1v1=(m1+m2)v2 [/b] [b]3. I tried a few different things, more or less throwing mud on the wall to see what sticks at minimum. But here goes… 1. Crossbow Dart KE= ½(1500N/m)(0.32m)^2= 76.8J 2. Solve for V1, ½(0.035kg)(v)^2=(1500N/m)(0.32)^2 ….Result 66.25 m/s 3. Solve for V2, (0.035kg)(66.25m/s)= (0.035kg + 5.1kg)v2 ….Result 0.451557 m/s …0.45 m/s 4. This is where I think I’m lost…delta KE/KE? Up to this point I hope this is right? [/b] Thank you all for the guidance [/QUOTE]
Insert quotes…
Post reply
Forums
Homework Help
Introductory Physics Homework Help
Conservation of Momentum- Inelastic Collisions
Back
Top