Those questions are connected, can someone please help me? Thank you! Block A is

Question

Those questions are connected, can someone please help me? Thank you!

Block A is released from rest at the center of a tank of water. The block accelerates upwara 1. At the instant the block is released, is the magnitude of the buoyant force on block A greater than, less than, or equal to the magnitude of its weight? Explain your reasoning When block A reaches the surface, it is observed to float at rest as shown in the diagram on the right. In this final position, is the buoyant force on block A greater than, less than, or equal to its weight? Explain your reasoning If 90% of block A lies below the surface of the water in its final position, then what is the density of block A? Explain/show your reasoning. 2. Final position of block A 3. Imagine that block A were released in the center of a tank filled with a fluid that is twice as dense as water. 4. Describe what will happen to block A after it is released. 5. Calculate the percentage of block A that is submerged after block A comes to rest Explain/show your reasoning

Explanation / Answer

A) :There are two forces acting on the block, one is its weight acting downwards and a buoyant force acting upwards. As the block is accelerating upwards which means that net force is upwards and thus we can say buoyant force is greater than its weight.

B) :here since block is at rest, which means that there is no acceleration And since acceleration is zero, so is the NET force. Thus buoyant force is equal to weight of the block.

C) :from buoyant force equation we have

Weight(mg) =rho *v*g

Where v is volume of water displaced.

Rho is density of water=1

Here 90% of block lies inside water which means that volume of water displaced is 90% of volume of block.

As mass=density x volume

Volume=m/d where d is density of bkock.

Here v=9/10(m/d).

Put values in above equation we have

mg=1*0.9m/d *g

d=0.9 that is the density of block.

D):as Fb=rho x vdisplacedxg

Then from above equation, as density gets increased by a factor of two, so gets the force. So net force will be two times th initial force.

When block is released it will come upwards with twice acceleration than it had in previous case.

E) :from the equation in part c , we have

mg=2rhox V xg

As mg was initially equal to rho x Vx g

So we have

RhoxVxg=2rhox v x g

v=V/2 i.e only 45% of block will remain submerged in water.

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.