Solving a Physics Problem Involving Two Blocks Connected by a Cord

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The problem involves two blocks, one on a surface and one hanging, connected by a cord over a pulley. The acceleration of the system was calculated to be 0.98 m/s², while the tension in the cord was found to be 35.28 N. The discrepancy with the book's answer of 0.1 m/s² suggests a possible typo. The calculations utilized the coefficient of kinetic friction and the forces acting on both blocks. The solution appears to be accurate based on the provided equations and values.
Edwardo_Elric
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Homework Statement


A block with mass 6.00kg resting on a horizontal surface is connected by a horizontal cord passing over a light frictionless pulley to a hanging block with mass 4.00kg. The coefficient of kinetic friction between the block and the horizontal surface is 0.50. After the blocks are released,
a.) Find the acceleration of each block
b.) The tension in the cord.


Homework Equations





The Attempt at a Solution


a.)
uk = 0.50
fk = ukN
fk = 0.50(6.00kg)(9.8m/s^2)
Summation of the mass of 6.00kg block
m1a = T - fk
m1a = T - 0.50(6.00kg)(9.8m/s^2)

Summation of the mass of 4kg block
m2a = m2g - T

so i add both the two forces:
m1a = T - 0.50(6.00kg)(9.8m/s^2)
+m2a = m2g - T
________________
(m1+m2)a = m2g - 0.50(6.00kg)(9.8m/s^2)
a = { (4.00kg)(9.8m/s^2) - 0.50(6.00kg)(9.8m/s^2) } / {6.00kg+4.00kg}
a = 0.98m/s^2

dont know how the back of the book got an answer of 0.1m/s^2

b.) m2a = m2g - T
(4.00kg)(.98m/s^2) = (4.00kg)(9.8) - T
T = 35.28N
 
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Your method and answers look correct to me. (Must be a typo in the book.)
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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