How Long Until Earth Collides with the Sun if its Orbit Stops?

[Benzoate]

Homework Statement

If the Earth were suddenly stopped in its orbit, how long would it take for it to collide with the sun?(Regard the sun as a fixed point mass. You may make use of the formula for the period of the Earth's orbit.

Homework Equations

tau=(4*pi^2*R^3/M*G)^.5

The Attempt at a Solution

Should I considered the velocity of the Earth before it came to a halt in its orbit? ; the radius between the two bodies are obviously not fixed. What do they mean when they say regard the sun as a fixed point mass?

 

[mgb_phys]

Should I considered the velocity of the Earth before it came to a halt in its orbit?

It says the Earth stopped, so no.

What do they mean when they say regard the sun as a fixed point mass?

It means just assume all the suns mass is at the centre, you don't have to worry about the mass near the edges of the sun pulling the Earth at a slightly different angle.
It 'probably' also means you work out the time for the centres to collide, not the time for the edge of the Earth to reach the outer edge of the sun.