CH 09 HW 22 of 22 roblem 9.69 Constants Part A At the county fair, Chris throws a 0.14 kg baseball at a 21 kg wooden milk bottle, hoping to knock it off its stand and win a prize The ball bounces straight back at 30 % of its incoming speed. knocking the bottle straight forward What is the bottl\'s speed, as a percentage of the ball\'s incoming speed? Express your answer using two significant figures. hottke atal) Submit
Solution
here,
mass of baseball , m1 = 0.14 kg
mass of wooden milk bottle , m2 = 2.1 kg
intial speed of ball be u
final speed of ball , v1 = - 0.3 * u
let the final speed of wooden milk bottle be v2
using conservation of momentum
m1 * u = m1 * v1 + m2 * v2
0.14 * u = - 0.14 * 0.3 * u + 2.1 * v2
solving for v2
v2 = 0.087 u
the percentage of initial velocity , % = 0.087 u/u * 100 = 8.7 %
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CH 09 HW 22 of 22 roblem 9-69 Constants Part A At the county fair- Chr.docx
1. CH 09 HW 22 of 22 roblem 9.69 Constants Part A At the county fair, Chris throws a 0.14 kg
baseball at a 21 kg wooden milk bottle, hoping to knock it off its stand and win a prize The ball
bounces straight back at 30 % of its incoming speed. knocking the bottle straight forward What
is the bottl's speed, as a percentage of the ball's incoming speed? Express your answer using
two significant figures. hottke atal) Submit
Solution
here,
mass of baseball , m1 = 0.14 kg
mass of wooden milk bottle , m2 = 2.1 kg
intial speed of ball be u
final speed of ball , v1 = - 0.3 * u
let the final speed of wooden milk bottle be v2
using conservation of momentum
m1 * u = m1 * v1 + m2 * v2
0.14 * u = - 0.14 * 0.3 * u + 2.1 * v2
solving for v2
v2 = 0.087 u
the percentage of initial velocity , % = 0.087 u/u * 100 = 8.7 %
