Solved Problem: Larry has a mass of 80 kg and runs across the front of the classroom with a speed of 4 m/s and jumps onto d The skateboard is initially at rest and a mass equal to Larry's. If friction with the floor is negligible, what is the speed of Larry and the skateboard after he jumps on board? Known: m = 80 kg, v, 4 m/s, m, = 80 kg, v = 0 m/s, Find the speed of Larry and the skateboard after the "collision." Principle: Momentum is conserved in an inelastic collision.

Principles of Physics: A Calculus-Based Text
5th Edition
ISBN:9781133104261
Author:Raymond A. Serway, John W. Jewett
Publisher:Raymond A. Serway, John W. Jewett
Chapter8: Momentum And Collisions
Section: Chapter Questions
Problem 49P
icon
Related questions
Question
Solved Problem: Larry has a mass of 80 kg and runs across the front of the classroom with a speed of 4 m/s and jumps onto a giant skateboard.
The skateboard is initially at rest and a mass equal to Larry's. If friction with the floor is negligible, what is the speed of Larry and the
skateboard after he jumps on board?
Known: m = 80 kg, v₁ = 4 m/s, m₂ = 80 kg, v = 0 m/s, Find the speed of Larry and the skateboard after the "collision."
li
Principle: Momentum is conserved in an inelastic collision.
?
?
?
?
V2,=0
+X
V1, V2, V
+X
Since both Larry and the skateboard end up with the
same speed, set v
V for simplicity sake.
lf =2f
Ap=Pf-Pi = 0 → Pi = Pf
mvi+mv2i = mv₁f + mv2f
m₁v₁i + 0 = m₁V + m₂ V
m1 vli = (m₁ + m₂)V
V =
Complete the calculation to show that the common velocity V = V₁₁
Consider an extreme case for v₁ = 4 m/s and v₂ = 0 m/s: m, = 8000 kg, m, = 80 kg, find V.
Find V for another extreme case for v = 4 m/s and v₂ = 0 m/s: m₁ = 80 kg, m₂ = 8000 kg.
Consider the case for v₁ = 4 m/s and v₂=-2 m/s: m₁ = 80 kg, m, = 80 kg, find V.
m1
m₁+m₂
Vli
This relationship for the final shared velocity V only works
when the struck object, has an initial velocity which is zero.
Transcribed Image Text:Solved Problem: Larry has a mass of 80 kg and runs across the front of the classroom with a speed of 4 m/s and jumps onto a giant skateboard. The skateboard is initially at rest and a mass equal to Larry's. If friction with the floor is negligible, what is the speed of Larry and the skateboard after he jumps on board? Known: m = 80 kg, v₁ = 4 m/s, m₂ = 80 kg, v = 0 m/s, Find the speed of Larry and the skateboard after the "collision." li Principle: Momentum is conserved in an inelastic collision. ? ? ? ? V2,=0 +X V1, V2, V +X Since both Larry and the skateboard end up with the same speed, set v V for simplicity sake. lf =2f Ap=Pf-Pi = 0 → Pi = Pf mvi+mv2i = mv₁f + mv2f m₁v₁i + 0 = m₁V + m₂ V m1 vli = (m₁ + m₂)V V = Complete the calculation to show that the common velocity V = V₁₁ Consider an extreme case for v₁ = 4 m/s and v₂ = 0 m/s: m, = 8000 kg, m, = 80 kg, find V. Find V for another extreme case for v = 4 m/s and v₂ = 0 m/s: m₁ = 80 kg, m₂ = 8000 kg. Consider the case for v₁ = 4 m/s and v₂=-2 m/s: m₁ = 80 kg, m, = 80 kg, find V. m1 m₁+m₂ Vli This relationship for the final shared velocity V only works when the struck object, has an initial velocity which is zero.
Expert Solution
steps

Step by step

Solved in 2 steps with 2 images

Blurred answer
Knowledge Booster
Helmholtz Free energy
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.
Similar questions
Recommended textbooks for you
Principles of Physics: A Calculus-Based Text
Principles of Physics: A Calculus-Based Text
Physics
ISBN:
9781133104261
Author:
Raymond A. Serway, John W. Jewett
Publisher:
Cengage Learning
Physics for Scientists and Engineers: Foundations…
Physics for Scientists and Engineers: Foundations…
Physics
ISBN:
9781133939146
Author:
Katz, Debora M.
Publisher:
Cengage Learning
College Physics
College Physics
Physics
ISBN:
9781285737027
Author:
Raymond A. Serway, Chris Vuille
Publisher:
Cengage Learning
Physics for Scientists and Engineers
Physics for Scientists and Engineers
Physics
ISBN:
9781337553278
Author:
Raymond A. Serway, John W. Jewett
Publisher:
Cengage Learning
Physics for Scientists and Engineers with Modern …
Physics for Scientists and Engineers with Modern …
Physics
ISBN:
9781337553292
Author:
Raymond A. Serway, John W. Jewett
Publisher:
Cengage Learning
Physics for Scientists and Engineers, Technology …
Physics for Scientists and Engineers, Technology …
Physics
ISBN:
9781305116399
Author:
Raymond A. Serway, John W. Jewett
Publisher:
Cengage Learning