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

AI Thread Summary
The discussion revolves around a physics problem involving two ice skaters and the principles of linear momentum and kinetic energy. Skater #1 throws skater #2, resulting in skater #2's velocity increasing to 9 m/s, while the final velocity of skater #1 needs to be calculated using conservation of momentum. Participants express confusion about the calculations, particularly regarding the change in kinetic energy and the impulsive forces acting on both skaters. The importance of understanding conservation laws and impulse in analyzing the scenario is emphasized. Overall, the thread highlights the complexities of applying these physics concepts in practical situations.
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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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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