An object under water has mass 100 kg. What is the buoyand force?

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The discussion centers on calculating the buoyant force on a 100 kg object submerged in water. The correct approach involves using the equation for weight, w=mg, leading to a calculated weight of 980 N. Participants suggest that the problem may contain a typo, possibly intending to state a mass of 1000 kg instead. The conversation confirms that the original calculations are accurate given the stated mass. The focus remains on clarifying the buoyant force based on the object's weight.
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An object is completely under water, hovering, neither rising nor sinking. Its mass is
100 kg. What is the buoyant force on the object, in Newtons?
(a) 12,460
(b) 17,860
(c) 16,080
(d) 9800
(e) none of these

Since buoyant force is equal to the weight of the object, I figured I could plug it into the equation w=mg
w=100 x 9.8
which would give me 980...
Am I doing something wrong?
 
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Nothing wrong with your work. I suspect a typo in the problem statement. Maybe they meant 1000 kg, not 100.
 
okay, thank you! :)
 
Thread 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
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