{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

445_Physics ProblemsTechnical Physics

# 445_Physics ProblemsTechnical Physics - Chapter 15 P15.21(a...

This preview shows page 1. Sign up to view the full content.

Chapter 15 447 P15.21 (a) E kA = 1 2 2 , so if ′ = A A 2 , ′ = = = E k A k A E 1 2 1 2 2 4 2 2 a f a f Therefore E increases by factor of 4 . (b) v k m A max = , so if A is doubled, v max is doubled . (c) a k m A max = , so if A is doubled, a max also doubles . (d) T m k = 2 π is independent of A , so the period is unchanged . *P15.22 (a) y y v t a t f i yi y = + + 1 2 2 = + + = = 11 0 0 1 2 9 8 22 9 8 1 50 2 m m s m s m s 2 2 . . . e j t t (b) Take the initial point where she steps off the bridge and the final point at the bottom of her motion. K U U K U U mgy kx k k g s i g s f + + = + + + + = + + = = e j e j a f 0 0 0 0 1 2 65 9 8 1 2 25 73 4 2 2 kg m s 36 m m N m 2 . . (c) The spring extension at equilibrium is x F k = = = 65 8 68 kg 9.8 m s 73.4 N m m 2 . , so this point is 11 8 68 19 7 + = . . m m below the bridge and the amplitude of her oscillation is
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Ask a homework question - tutors are online