Adog, with a mass of 10.0 kg, is standing on a flatboat so that he is 22.5 m from the shore. he walks 7.8 m on the boat toward the shore and then stops. the boat has a mass of 46.0 kg. assuming there is no friction between the boat and the water, how far is the dog from the shore now?

16.096

Explanation:

Given

mass of dog

mass of boat

distance moved by dog relative to ground=

distance moved by boat relative to ground=

Distance moved by dog relative to boat=7.8m

There no net force on the system therefore centre of mass of system remains at its position

0=

0=

i.e. boat will move opposite to the direction of dog

Now

substitutingvalue

now the dog is  22.5-6.403=16.096m from shore

the working equation for the angular size is the product of the physical size and 360 degrees divided by the product of two pi and distance from earth. the minimum size would be 0.559 degrees while the maximum size would be 0.49 degrees. 

dang that balls went far