The lower end of a long plastic straw is immersed below the surface of the water

Question

The lower end of a long plastic straw is immersed below the surface of the water in a plastic cup. An average person sucking on the upper end of the straw can pull water into the straw to a vertical height of 1.1 m above the surface of the water in the cup. Find the lowest gauge pressure that the average person can achieve inside their lungs.

A rock has mass 1.80 kg. When the rock is suspended from the lower end of a string and totally immersed in water, the tension in the string is 12.4 N .What is the smallest density of a liquid in which the rock will float?

Explanation / Answer

Here , for question 1)

height of straw , h = 1.1 m

gauge pressure = - p * g * h

gauge pressure = -1000 * 9.8 * 1.1

gauge pressure = -10780 Pa

the lowest gauge pressure that the average person can exert is -10780 Pa

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

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