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This is a qualitative q from kaplan, but if i had to solve for it, this is probably how i'd do it
Two wooden balls of equal volume, but different density are held beneath the surface of water. Ball A --density =.5g/cm3 Ball B-.7g/cm3, once released, they accelerate upwards. identify their acceleration relation.
Ball A , Fb-W=m*a , Fb=m*a+W, similarly Fb =m'*b +W' (,a'w',m'- ball b)
Since the Fb is identical, m*a+W =m*a+W' , m(a+g) =m'(a'+g)
m/m' =(a'+g)/(a+g)
d/d' = a'/a (g doesnt cancel, but they add the same value, so ignored it for simplicity)
a' = some fraction of a
Is this right
I do know that the mass of A should be less than mass of B(d=m/v ,equal v, higher density = larger mass) and F=ma dictates that the a of mass A will be higher, but just wanted to check my understanding.
Is there a better way to solve a problem like this one, if it actually needs to be solved
thanks
Two wooden balls of equal volume, but different density are held beneath the surface of water. Ball A --density =.5g/cm3 Ball B-.7g/cm3, once released, they accelerate upwards. identify their acceleration relation.
Ball A , Fb-W=m*a , Fb=m*a+W, similarly Fb =m'*b +W' (,a'w',m'- ball b)
Since the Fb is identical, m*a+W =m*a+W' , m(a+g) =m'(a'+g)
m/m' =(a'+g)/(a+g)
d/d' = a'/a (g doesnt cancel, but they add the same value, so ignored it for simplicity)
a' = some fraction of a
Is this right
I do know that the mass of A should be less than mass of B(d=m/v ,equal v, higher density = larger mass) and F=ma dictates that the a of mass A will be higher, but just wanted to check my understanding.
Is there a better way to solve a problem like this one, if it actually needs to be solved
thanks
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