Question 1

If you sit in a boat near the edge of a river channel, you might notice the water moving more quickly on the side away from the shore (the channel side). If you are initially moving with the river, you will be pushed

Accepted Answer

Water pressure is larger on the shore side due to the slower movement of water there, pushing the boat into the channel where the water moves more quickly.

Question 2

A boat floating in a large pool is loaded with wood blocks. The water level at the pool's edge is marked with a red line. The blocks are now thrown overboard and float outside the boat. When the water becomes calm again,

Accepted Answer

When the wood blocks are thrown overboard, the water level will rise because the blocks displace water equal to their weight. However, since the blocks were already floating in the boat and not adding any weight to the system, the water level would have risen the same amount when they were still in the boat. Therefore, when the blocks are removed from the boat, the water level will return to its original level, which is marked by the red line. Therefore, the answer is C.

Question 3

The skinny tires of a 10-speed racing bicycle require more air pressure than the fat tires on an equally massive mountain bike because

Accepted Answer

The pressure inside a tire is defined as the force per unit area that the tire exerts on the ground. The racing bike has skinny tires which touch the ground over a smaller area than the mountain bike's fat tires. Therefore, the force per unit area is greater in the racing bike's tires, requiring more air pressure to support its weight and provide stability on the road.

Question 4

A child is drinking a liquid with a straw. Which of the following statements is true?

Accepted Answer

When a child drinks liquid through a straw, the pressure is reduced inside the straw by sucking air out of it. This reduction in pressure causes atmospheric pressure on the surface of the liquid to push it up the straw and into the child's mouth. This phenomenon is known as suction.

Option A is incorrect because the fluid is not being pulled up into the straw, but rather pushed up by atmospheric pressure.

Option B is incorrect because the pressure inside the straw decreases as the length of the straw increases.

Option C is incorrect because the pressure inside the straw is not affected by the viscosity of the liquid.

Question 5

One morning you discover that a tire on your auto is in need of air. As you add air to the tire, which of the following statements is true?

Accepted Answer

When air is added to a tire, the volume of the tire remains the same while the number of air molecules inside the tire increases. This leads to an increase in pressure, as there are now more molecules colliding with the tire walls, creating a greater force per unit area. The density of the air inside the tire remains the same, as the mass and volume of the air both increase proportionally. Therefore, only statement B is true.

Question 6

Three individuals stand with all of their weight on the heel of one foot: a man of weight 600 N and a heel area of 100 cm², a child of weight 200 N and a heel area of 25 cm², and woman of weight 450 N and a heel area of 2 cm². The one exerting the least pressure on the ground is

Accepted Answer

Pressure is defined as force (or weight in this context) divided by the area over which the force is distributed. The man has the largest area (100 cm^2) for his weight (600 N), resulting in the lowest pressure compared to the child and the woman, who have smaller areas for their respective weights.

Question 7

If you hold a light tissue in your hands and gently blow across its top, the tissue will rise slightly because

Accepted Answer

When air moves, its pressure decreases due to Bernoulli's Principle. This means that the pressure below the tissue is greater than the pressure above it, causing the tissue to rise.

Question 8

Hot coffee is poured into a cylindrical container until it is nearly full. The container is immediately sealed by stretching a rubber balloon across the container mouth and tightly sealing the edges. Twenty minutes later, you observe that the still intact rubber seal

Accepted Answer

The answer of Hot coffee is poured into a cylindrical...

Question 9

A silver dollar, a quarter, and a penny(these are in order of decreasing diameter) lie at the bottom of a wishing well filled with water. The coin experiencing the largest downward force on its top surface due to the water pressure is the

Accepted Answer

The downward force experienced by a coin due to water pressure depends on the surface area of the coin in contact with the water. The larger the surface area, the larger the downward force. Since the silver dollar has the largest surface area, it will experience the largest downward force, followed by the quarter and then the penny. Therefore, the correct choice is A) silver dollar.

Question 10

A clown at the circus blows up a balloon with helium. This balloon will not float to the ceiling unless

Accepted Answer

The balloon will float if the combined weight of the balloon and the helium is less than the weight of the air displaced by the balloon, which is a principle of buoyancy.

Question 11

An ice cube in a glass of water is pushed to the bottom of the glass and held there with a straw. Consequently, the buoyant force on the ice cube is now

Accepted Answer

The answer of An ice cube in a glass of...

Question 12

A boat floating in a large pool is loaded with solid iron bars. The water level at the pool's edge is marked with a red line. The iron is now thrown overboard. When the water becomes calm again,

Accepted Answer

When the iron bars are in the boat, they displace a volume of water that weighs the same as the bars. When thrown overboard, they displace only their own volume, which is less than the volume they displaced when in the boat, because iron is denser than water. Therefore, the water level decreases.

Question 13

An iceberg is floating in the ocean with 10% of its volume extending above the ocean's surface. What can you say about the iceberg?

Accepted Answer

An iceberg floats because it displaces an amount of water equal to its weight. Therefore, if 10% of the iceberg is above water, 90% is below water. This means that the density of the iceberg must be slightly less than the density of water. So, Option D is correct.

Question 14

If the atmospheric pressure is 15 lb/in², what is the corresponding downward force on the top of a horizontal square area 5 inches on each side?

Accepted Answer

The downward force can be calculated by multiplying the pressure by the area. The area of the square is 5 inches * 5 inches = 25 square inches. The pressure is 15 lb/in^2, so the total force is 15 lb/in^2 * 25 in^2 = 375 lbs.

Question 15

It is observed that, as bubbles rise in a deep column of water, the diameter of the bubbles increases. This is best explained by

Accepted Answer

Boyle's Law states that the volume of a gas at a constant temperature is inversely proportional to its pressure. As bubbles rise in a deep column of water, the pressure exerted on the bubbles decreases due to the weight of the water above. According to Boyle's Law, as the pressure decreases, the volume of the gas (i.e. the bubble) will increase, leading to an increase in diameter.

Question 16

Archimedes' Principle states that...

Accepted Answer

Archimedes' Principle specifically states that the buoyant force on an object immersed in a fluid is equal to the weight of the displaced fluid. Therefore, choice A is the correct answer. Choices B, C, and D describe other principles related to fluids, but are not correct statements of Archimedes' Principle.

Question 17

A sharp knife can more easily cut objects than can a dull knife because

Accepted Answer

A sharp knife has a thinner edge which reduces the surface area in contact with the object being cut. This reduces the pressure required to cut through the object, making it easier to cut. A dull knife, on the other hand, has a wider edge, which means more surface area in contact with the object being cut, requiring more force to cut through it. Therefore, a greater pressure can be applied with a sharp knife, making it easier to cut objects.

Question 18

A hot air balloon derives its lift from the property of fluids as stated by

Accepted Answer

Archimedes' Principle states that an object immersed in fluid experiences a buoyant force equal to the weight of the fluid it displaces. In the case of a hot air balloon, the hot air inside the balloon is less dense than the cooler air outside, resulting in a buoyant force that allows the balloon to float.

Question 19

An ant and an elephant are walking through the jungle. On which does the greater buoyant force act?

Accepted Answer

The buoyant force acting on an object depends on the volume of fluid it displaces. Since an elephant displaces more air (or any fluid they might be walking through) than an ant due to its larger size, the greater buoyant force acts on the elephant.

Question 20

A balloon inflated with helium is able to float toward the ceiling because

Accepted Answer

The balloon and the gas it contains weigh less than the air displaced by the balloon. This means that the combined weight of the balloon and the helium gas is less than the weight of the same volume of air that it displaces. As a result, the balloon and the gas rise towards the ceiling because of the upward force of the displaced air, known as buoyancy.

Quiz 9: The Behavior of Fluids

If you sit in a boat near the edge of a river channel, you might notice the water moving more quickly on the side away from the shore (the channel side) . If you are initially moving with the river, you will be pushed

A boat floating in a large pool is loaded with wood blocks. The water level at the pool's edge is marked with a red line. The blocks are now thrown overboard and float outside the boat. When the water becomes calm again,

The skinny tires of a 10-speed racing bicycle require more air pressure than the fat tires on an equally massive mountain bike because

A child is drinking a liquid with a straw. Which of the following statements is true?

One morning you discover that a tire on your auto is in need of air. As you add air to the tire, which of the following statements is true?

Three individuals stand with all of their weight on the heel of one foot: a man of weight 600 N and a heel area of 100 cm², a child of weight 200 N and a heel area of 25 cm², and woman of weight 450 N and a heel area of 2 cm². The one exerting the least pressure on the ground is

If you hold a light tissue in your hands and gently blow across its top, the tissue will rise slightly because

Hot coffee is poured into a cylindrical container until it is nearly full. The container is immediately sealed by stretching a rubber balloon across the container mouth and tightly sealing the edges. Twenty minutes later, you observe that the still intact rubber seal

A silver dollar, a quarter, and a penny(these are in order of decreasing diameter) lie at the bottom of a wishing well filled with water. The coin experiencing the largest downward force on its top surface due to the water pressure is the

A clown at the circus blows up a balloon with helium. This balloon will not float to the ceiling unless

An ice cube in a glass of water is pushed to the bottom of the glass and held there with a straw. Consequently, the buoyant force on the ice cube is now

A boat floating in a large pool is loaded with solid iron bars. The water level at the pool's edge is marked with a red line. The iron is now thrown overboard. When the water becomes calm again,

An iceberg is floating in the ocean with 10% of its volume extending above the ocean's surface. What can you say about the iceberg?

If the atmospheric pressure is 15 lb/in², what is the corresponding downward force on the top of a horizontal square area 5 inches on each side?

It is observed that, as bubbles rise in a deep column of water, the diameter of the bubbles increases. This is best explained by

Archimedes' Principle states that...

A sharp knife can more easily cut objects than can a dull knife because

A hot air balloon derives its lift from the property of fluids as stated by

An ant and an elephant are walking through the jungle. On which does the greater buoyant force act?

A balloon inflated with helium is able to float toward the ceiling because

Quiz 9: The Behavior of Fluids

If you sit in a boat near the edge of a river channel, you might notice the water moving more quickly on the side away from the shore (the channel side) . If you are initially moving with the river, you will be pushed

A boat floating in a large pool is loaded with wood blocks. The water level at the pool's edge is marked with a red line. The blocks are now thrown overboard and float outside the boat. When the water becomes calm again,

The skinny tires of a 10-speed racing bicycle require more air pressure than the fat tires on an equally massive mountain bike because

A child is drinking a liquid with a straw. Which of the following statements is true?

One morning you discover that a tire on your auto is in need of air. As you add air to the tire, which of the following statements is true?

Three individuals stand with all of their weight on the heel of one foot: a man of weight 600 N and a heel area of 100 cm2, a child of weight 200 N and a heel area of 25 cm2, and woman of weight 450 N and a heel area of 2 cm2. The one exerting the least pressure on the ground is

If you hold a light tissue in your hands and gently blow across its top, the tissue will rise slightly because

Hot coffee is poured into a cylindrical container until it is nearly full. The container is immediately sealed by stretching a rubber balloon across the container mouth and tightly sealing the edges. Twenty minutes later, you observe that the still intact rubber seal

A silver dollar, a quarter, and a penny(these are in order of decreasing diameter) lie at the bottom of a wishing well filled with water. The coin experiencing the largest downward force on its top surface due to the water pressure is the

A clown at the circus blows up a balloon with helium. This balloon will not float to the ceiling unless

An ice cube in a glass of water is pushed to the bottom of the glass and held there with a straw. Consequently, the buoyant force on the ice cube is now

A boat floating in a large pool is loaded with solid iron bars. The water level at the pool's edge is marked with a red line. The iron is now thrown overboard. When the water becomes calm again,

An iceberg is floating in the ocean with 10% of its volume extending above the ocean's surface. What can you say about the iceberg?

If the atmospheric pressure is 15 lb/in2, what is the corresponding downward force on the top of a horizontal square area 5 inches on each side?

It is observed that, as bubbles rise in a deep column of water, the diameter of the bubbles increases. This is best explained by

Archimedes' Principle states that...

A sharp knife can more easily cut objects than can a dull knife because

A hot air balloon derives its lift from the property of fluids as stated by

An ant and an elephant are walking through the jungle. On which does the greater buoyant force act?

A balloon inflated with helium is able to float toward the ceiling because

Three individuals stand with all of their weight on the heel of one foot: a man of weight 600 N and a heel area of 100 cm², a child of weight 200 N and a heel area of 25 cm², and woman of weight 450 N and a heel area of 2 cm². The one exerting the least pressure on the ground is

If the atmospheric pressure is 15 lb/in², what is the corresponding downward force on the top of a horizontal square area 5 inches on each side?