What is the magnitude of the net force acting on the kayak?

AI Thread Summary
The discussion revolves around calculating the net force acting on a kayak and the gravitational force experienced by an object falling near a neutron star. For the neutron star scenario, the gravitational force can be calculated using the equation Fg = G(mMn/Rn^2), but participants express confusion about applying it. The kayak problem involves determining the net force using the formula F = ma, where the acceleration and mass are known. Participants seek clarification on how to apply these equations effectively. Overall, the thread highlights the challenges of applying physics concepts to specific scenarios.
Marcelgluch
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neutron star has a mass of 2.0 x 10^30 kg, and a radius of 5.0 x 10^3 m
suppose an object falls from rest near the surface of such a star. how fast would it be moving after it had fallen a distance of 0.010 m? (gravity constant over star, and star is not rotating)


and

a person in a kayak starts paddling, and it accelerates from 0 to 0.60 in a distance of 0.41 m if combined mass of person and kayak is 73 kg what is the magnitude of the net force acting on the kayak?
 
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Please show some work. The first question requires the equation for gravitational force, the second asks you to use the definition of force.
 
my prof wrote down some equations for the first one

Fg = G(mMn/Rn^2 = m(GMn/ Rn^2)

and then

Fg = mabut I am not sure about the second one...thats mainly why I am asking.. is because i don't know how to do it...
 
Marcelgluch said:
my prof wrote down some equations for the first one

Fg = G(mMn/Rn^2 = m(GMn/ Rn^2)

and then

Fg = ma


but I am not sure about the second one...thats mainly why I am asking.. is because i don't know how to do it...

Both are correct. They allow you to determine the acceleration a from knowledge of the other variables in the first equation.
 
okay.. but still don't know how to solve it..
 
k i think i get the second one.. but the neutron star one still is a no go
 
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