Force and Pressure in Fluids

When you increase your depth under water, the water pressure on your body

• increases

• decreases

• stays the same

Why won't you sink in mud if you wear boots?

• Because the surface area is larger creating less pressure.

• Has air in it to keep you floating.

• Because the mud won't want you.

Diagram shows the design of a dam. Why does the thickness of the dam increase with its depth?

• The design of this structure is stronger.

• Water pressure increases with depth.

• The cost of construction is lower.

• Water pressure acts uniformly in all directions.

Tags

NGSS.MS-ETS1-1

An object will float on water if it is

• less dense than water.

• more dense than water.

• the same density as water.

A fluid can be...

• a gas
• a liquid
• a liquid or a gas
• a solid

When blood pressure is measured, the cuff of the sphygmomanometer is wrapped round the upper arm and must be held at the level of the heart. Why?

• Blood pressure depends on the level of the blood.

• Blood pressure is normal when the cuff and heart are at the same level.

• Blood is able to flow easily to the wrist.

The pressure of sea water at the bottom of the sea is 1.2 × 108 N m–2.

Determine the depth of the sea.

[Density of sea water = 1020 kg m^–3]

• 1.18×10⁴ m

• 1.18×10⁵ m

• 1.18×10⁶ m

• 1.18×10⁹ m

Tags

NGSS.HS-PS2-4

Diagram shows a U-tube filled with two liquids, X and Y which are immiscible. The heights of the liquid columns of X and Y from level P are 8 cm and 4 cm respectively. Which of the following statements is true?

• The density of X is less than the density of Y.

• The liquid pressure is higher in column X than in column Y at level P.

• The densities of liquids X and Y are equal.

Tags

NGSS.MS-PS2-4

A submarine has a surface area of 300 m².

The density of sea water is 1050 kg m^–3.

At what depth under the sea, will the additionalpressure on the submarine be 5 × 10⁵ Pa?

[Take g = 10 N kg^–1]

• 47.62 m

• 67.62 m

• 87.62 m

• 57.62 m

Tags

NGSS.HS-PS2-4

The figure below shows a reservoir on a hill. The reservoir supplies water to a water tank on a tall building.

Calculate the water pressure at X.

(Density of water = 1000 kg m^–3)

• 1.4×10⁹ Nm^–2

• 1.4×10² Nm^–2

• 1.4×10⁵ Nm^–2

• 1.4×10⁸ Nm^–2