HomeworkLib
Question

Jack and Annie are standing facing each other on frictionless ice at position x=0. They give...

Jack and Annie are standing facing each other on frictionless ice at position x=0. They give each other a sharp push, so that after they have contact Jack is moving in the negative x direction with a speed of 5 m/s. Jack has a mass of 60kg and Annie has a mass of 40kg. What is the position of their center of mass after 4 seconds?
science   physics   
0 0
Add a comment Improve this question Transcribed image text
Next > < Previous
Sort answers by oldest

Homework Answers

Answer #1

let the speed of annie after pushing be v m/s

By the conservation of momentum

m1u1 = m2u2

60*5 = 40*v

v = 7.5 m/s

position of jamie after 4 s = -5*4 = -20 m

position of annie after 4s = 7.5*4 = 30 m

position of centre of mass = m1x1 + m2x2 / m1 + m2

= 60*-20 + 40*30 / ( 60 + 40)

= 0

so the position of COM after 4s is x =0

0 0
Add a comment
Know the answer?
Add Answer to:
Jack and Annie are standing facing each other on frictionless ice at position x=0. They give...
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for? Ask your own homework help question. Our experts will answer your question WITHIN MINUTES for Free.
Similar Homework Help Questions

  • Three ice skaters meet at the center of a rink and each stand at rest facing...

    Three ice skaters meet at the center of a rink and each stand at rest facing the center, within arm’s reach of the other two. On a signal, each skater pushes himself away from the other two across the frictionless ice. After the push, skater A with mass mA = 80.0 kg moves in the negative y-direction at 3.50 m/s and skater B with mass mB = 75.0 kg moves in the negative x-direction at 4.00 m/s. Find the x-...

  • Three ice skaters meet at the center of a rink and each stands at rest facing...

    Three ice skaters meet at the center of a rink and each stands at rest facing the center, within arm's reach of the other two. On a signal, each skater pushes himself away from the other two across the frictionless ice. After the push, skater A with mass mA = 80.0 kg moves in the negative y-direction at 4.00 m/s and skater B with mass mB = 85.0 kg moves in the negative x-direction at 3.00 m/s. Find the x-...

  • Three ice skaters meet at the center of a rink and each stands at rest facing...

    Three ice skaters meet at the center of a rink and each stands at rest facing the center, within arm's reach of the other two. On a signal, each skater pushes himself away from the other two across the frictionless ice. After the push, skater A with mass mA = 75.0 kg moves in the negative y-direction at 4.00 m/s and skater B with mass mB = 80.0 kg moves in the negative x-direction at 3.50 m/s. Find the x-...

  • QUESTION 1 Two skaters, one of mass 80 kg, the other of mass 40 kg, are...

    QUESTION 1 Two skaters, one of mass 80 kg, the other of mass 40 kg, are standing next to each other on frictionless ice rink. The 40 kg skater pushes the 80 kg skater. After the push, the 80 kg skater is going at 1 m/s. How fast and in what direction is the 40 kg skater going after the push? (HINT: use the fact that since there are no external forces, the velocity of the center of mass of...

  • Two ice skaters stand facing each other at rest on a frozen pond. They push off...

    Two ice skaters stand facing each other at rest on a frozen pond. They push off against one another and the 48-kg skater acquires a speed of 0.69 m/s. If the other skater acquires a speed of 0.87 m/s, what is her mass? ____kg

  • how to do this question? While Standing on frictionless ice, you (mass 65.0 kg) toss a...

    how to do this question? While Standing on frictionless ice, you (mass 65.0 kg) toss a 4.50 kg rock with initial speed 12.0 m/s. The rock is 15.2 m from you when it lands. Take the x axis on the ice surface in the horizontal direction of the motion of the rock. Ignore the initial height of the toss. Part A At what angle did you toss it? Part B How fast are you moving? |v| =

  • 4:15 PM Thu 21 Nov webassignet 13. +-12 points SerCP11GE 6.P.030. My Notes Ask Your Teacher...

    4:15 PM Thu 21 Nov webassignet 13. +-12 points SerCP11GE 6.P.030. My Notes Ask Your Teacher Three ice skaters meet at the center of a rink and each stands at rest facing the center, within arm's reach of the other two. On a signal, each skater pushes himself away from the other two across the frictionless ice. After the push, skater A with mass ma - 70.0 kg moves in the negative y-direction at 2.00 m/s and skater B with...

  • #4-7 Two ice skaters stand facing each other at rest on a frozen pond. They push...

    #4-7 Two ice skaters stand facing each other at rest on a frozen pond. They push off against one another and the 48 kg skater acquires a speed of 0.69 m/s If the other skater acquires a speed of 0.81 m/s, what is her mass in kilograms? kg My Notes Ask Your Teacher -/2 points HAFColPhys1 8.2WA019. O5 Submissiens Used A man holding a rock sits on a sled that is sliding across a frozen lake (negligible friction) with a...

  • Three people standing on a frictionless surface are initially at rest. After pushing off of each...

    Three people standing on a frictionless surface are initially at rest. After pushing off of each other, person A (mass = m) moves off with a speed of at an angle of degrees from the positive x direction. Person B (mass = 2m) moves off with a speed of v in the negative y direction. Which expression gives the final momentum of person C? O-mu cos 0 € + (2mv + mv sin 0) O-mv cos @ + (2mv –...

  • Two boys are sliding toward each other on a frictionless, ice-covered parking lot. Jacob, mass 45...

    Two boys are sliding toward each other on a frictionless, ice-covered parking lot. Jacob, mass 45 kg, is gliding to the right at 8.02 m/s, and Ethan, mass 31.0 kg, is gliding to the left at 10.5 m/s along the same line. When they meet, they grab each other and hang on. (a) What is their velocity immediately thereafter? b) What fraction of their original kinetic energy is still mechanical energy after their collision? (c) That was so much fun...

ADVERTISEMENT
Free Homework Help App
Download From Google Play
Scan Your Homework
to Get Instant Free Answers
Need Online Homework Help?
Ask a Question
Get Answers For Free
Most questions answered within 3 hours.
ADVERTISEMENT
ADVERTISEMENT