Two spherical stars and have densities and , respectively. and have the same radius, and their masses and are related by . Due to an interaction process, star loses some of its mass, so that its radius is halved, while its spherical shape is retained, and its density remains . The entire mass of lost by is deposited as a thick spherical shell on with the density of the shell being . If and are the escape velocities from and after the interaction process, the ratio the value of is ____.
Answer:
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Written solution
Step 1: Determine the mass and radius of star after the interaction.
The radius of star is halved while its density remains constant, meaning its volume is reduced by a factor of .
Step 2: Calculate the mass lost by star .
Subtract the final mass of star from its initial mass.
Step 3: Determine the new radius of star .
The lost mass is deposited as a shell of density on star , which initially has radius .
Step 4: Determine the new mass of star .
Add the deposited mass to the initial mass of star , where .
Step 5: Write the expressions for the escape velocities.
Use the formula for escape velocity .
Step 6: Calculate the ratio of the escape velocities.
Divide by and simplify the expression.
Step 7: Solve for .
Equate the calculated ratio to the given expression.
Answer: