A fisherman and his young niece are in a boat on a small pond. Both are wearing

Question

A fisherman and his young niece are in a boat on a small pond. Both are wearing life jackets. The niece l is holding a large helium filled balloon by a string. Consider each action below independently and indicate whether the level of the water in the pond Rises, Falls, is Unchanged or Cannot tell. The niece pops the helium balloon. The niece finds a cup and bails some water out of the bottom of the boat. The niece gets in the water, looses her grip on the string, letting the balloon escape upwards. The fisherman lowers the anchor and it hangs one foot above the bottom of the pond. The fisherman lowers himself in the water and floats on his back. The fisherman knocks the tackle box and it sinks to the bottom.

Explanation / Answer

Concelpt is, more the buoyant from water, higher is the water level. To identify buoyant force, we should find amount of mass suppoted by water. More is the mass resting on water more is buoyant force.

1) & 3) Helium Balloon is pulling the girl upward, as a result part of girl's weight is supported by water. As it pops or is released in the air, complete weight of girl is on water. So level rises.

2) Weight floating on water remain same. water in the boat or in pond does not make any difference. Water level remains same.

4) Anchor is not touching the bottom of pond, weight floating remains same. So no change in water level.

5) Fisherman is floating in the water or is in the boat, it's weight is supported by buoyant force. Water level remains same.

6) As box sinks to the bottom, part of it's weight is balanced by reaction from the bottom. Hence buoyant force goes down. So level falls.

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

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