Linear Momentum, Impulse, Center of a Mass, Velocity, Kinetic Energy

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SUMMARY

The discussion focuses on the physics concepts of linear momentum, impulse, and kinetic energy through a problem involving two ice skaters. Initially, both skaters travel at 4.5 m/s, but after skater #1 throws skater #2, the latter reaches a speed of 9 m/s. The final velocity of skater #1 is determined using the conservation of momentum, resulting in a velocity of 0.75 m/s to the left. The total kinetic energy decreases due to the throw, indicating a loss of energy, and the impulsive force on skater #2 is calculated based on the change in momentum over the time of the throw.

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  • Knowledge of impulse and its calculation
  • Familiarity with kinetic energy concepts
  • Basic algebra for solving equations
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  • Learn how to calculate impulse and its effects on motion
  • Explore the relationship between kinetic energy and momentum
  • Investigate real-world applications of these physics concepts in sports
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DMRika
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Homework Statement



Two ice skaters (m1 = 85kg and m2 = 52kg) in a pairs-skating tournament are both initially holding on to each other while travling to the right at 4.5 m/s. Skater #1 then thows skater #2 to the right in a graceful toss. Immediately afterward, skater #2 is travling to the right at 9 m/s (ignore friction).

a. What is the final velocity of skater #1? Is it to the right or left?

b. What was the change in total kinetic energy of the skaters due to the throw? Was net kinetic energy gained or lost?

c. If the throw took .5s, what was the magnitude of the impulsive force on skater #2?

d. Was the impulsive force acting on skater #1 was less than, the same as, or greater than the force on skater #2?

e. Find the final velocity (after the throw) of the center-of-mass of the two skaters.

Homework Equations


Not sure

The Attempt at a Solution



a. I thought skater #1 would be traveling at 2.25 m/s to the right. If he threw skater #2 as to increase her speed by half, then his speed should be reduced by half.

Didn't understand the rest of the questions.
 
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Welcome to PF!

Hi DMRika! Welcome to PF! :smile:
DMRika said:
Two ice skaters (m1 = 85kg and m2 = 52kg) in a pairs-skating tournament are both initially holding on to each other while travling to the right at 4.5 m/s. Skater #1 then thows skater #2 to the right in a graceful toss. Immediately afterward, skater #2 is travling to the right at 9 m/s (ignore friction).

a. What is the final velocity of skater #1? Is it to the right or left?

a. I thought skater #1 would be traveling at 2.25 m/s to the right. If he threw skater #2 as to increase her speed by half, then his speed should be reduced by half.

No, it doesn't work like that. :redface:

Use conservation of https://www.physicsforums.com/library.php?do=view_item&itemid=53"
b. What was the change in total kinetic energy of the skaters due to the throw? Was net kinetic energy gained or lost?

Didn't understand the rest of the questions.

What is the definition of https://www.physicsforums.com/library.php?do=view_item&itemid=132" ?
 
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