Hi, i need help with this problem. I followed the steps from thetextbook, but fo

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Hi, i need help with this problem. I followed the steps from thetextbook, but for some reason i kept on getting it wrong.
Suppose our sun eventually collapses into a white dwarf, inthe process losing about 3/4 of its mass and winding up with aradius 3.0 percent of its existing radius.
a. what would its rotation rate be? (take the sun's currentperiod to be about 30 days)
T1 = 30 days, Final Mass = 3/4M, Radius = 0.03R
L1=L2 I1*1 = I2 *2 2/5MR^2 x 2 pi/T1 = 2/5 x 3/4M x 0.03^2 x 2pi/T2 T2 = 3/10 x (9x10^-4) x T1 T2 = (0.30x(9x10^-4)x30) days = 0.0081 days x (24 hr/day)x(3600s/hr) = 699.84 s
angular speed 2 = 2pi/T2 = 2pi/699.84s = 9.0 x10^-3
b. what would be its final KE in terms of its initial KE oftoday?
KE2 = 1/2*I2*(2^2) KE2 = 1/2*(2/5x3/4m x (0.03)^2) x (2pi/T2)^2 KE2 = (1/2x2/5MR^2 x (2pi)2) x 1/2 x 3/10 x (9.0x10^-4) x(1/0.0081)^2 KE2 = KE x 30^2 x (2/7x10^-4/2) x (1.0.0081)^2 = 1.9 x 10^3KE

Suppose our sun eventually collapses into a white dwarf, inthe process losing about 3/4 of its mass and winding up with aradius 3.0 percent of its existing radius.
a. what would its rotation rate be? (take the sun's currentperiod to be about 30 days)
T1 = 30 days, Final Mass = 3/4M, Radius = 0.03R
L1=L2 I1*1 = I2 *2 2/5MR^2 x 2 pi/T1 = 2/5 x 3/4M x 0.03^2 x 2pi/T2 T2 = 3/10 x (9x10^-4) x T1 T2 = (0.30x(9x10^-4)x30) days = 0.0081 days x (24 hr/day)x(3600s/hr) = 699.84 s
angular speed 2 = 2pi/T2 = 2pi/699.84s = 9.0 x10^-3
b. what would be its final KE in terms of its initial KE oftoday?
KE2 = 1/2*I2*(2^2) KE2 = 1/2*(2/5x3/4m x (0.03)^2) x (2pi/T2)^2 KE2 = (1/2x2/5MR^2 x (2pi)2) x 1/2 x 3/10 x (9.0x10^-4) x(1/0.0081)^2 KE2 = KE x 30^2 x (2/7x10^-4/2) x (1.0.0081)^2 = 1.9 x 10^3KE

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