CHAPTERS 11-14: VIDEO ASSIGNMENT Flashcards
What happens when Dr. Hewitt places a card on a glass full of colored water and turns it upside down?
The card stays, and the water also stays in the glass.
Why do the card and water do what they do when Dr. Hewitt flips them over?
The card is held up by atmospheric pressure that balances the weight of water.
What happens when Dr. Hewitt takes the cans containing a small amount of hot water and dips them in cold water?
The cans get crushed.
Why do the cans containing a small amount of hot water do what they do in the experiment when Dr. Hewitt immerses them?
When the cans are suddenly cooled, the pressure inside them is less than the atmospheric pressure outside.
Consider the set of tubes shown in the figure. Each tube contains an unknown fluid that is less dense than the water it floats on top of. Rank the four unknown fluids from least dense to most dense.
Least dense: A,C
In between: B
Most dense: D
Rank, from smallest to largest, the pressures in the tank of motionless fluid shown in the figure.
Smallest: A
Somewhat small: B,C,D
Somewhat large: E
Largest: F
When Dr. Hewitt immerses the object in water, how does the loss of weight of the object compare with the buoyant force of the water?
Loss of weight is equal to the buoyant force.
When Dr. Hewitt immerses an object in water the second time and catches the water that is displaced by the object, how does the weight lost by the object compare to the weight of the water displaced?
The weight loss of the object is equal to the weight of the water displaced.
What is the buoyant force that acts on a submerged object equal to?
The buoyant force is equal to the weight of the fluid displaced by the submerged object.
Suppose that we repeat the experiment shown in the video, but we replace one of the cylinders with a cylinder that has twice the radius (and use larger containers of water). If the height of the original cylinder is h , how deeply must we submerge the new cylinder to get the same weight reduction as in the video?
1/4 h
Consider the video tutorial you just watched. Suppose we repeat the experiment, but this time place the divider closer to one side of the tube than to the other. How will the speed of the air on the wide and narrow sides of the divider compare? (Assume that burning has a negligible effect on the mass of the air circulating through the tube.)
The air will move faster on the narrow side.
A strong wind blows over the house shown in the figure. The wind is much stronger over the house’s roof than lower down, and the house has an open chimney. A window on the ground floor is open, and so are the doors inside the house. Which way will air flow through the house?
In the window and out the chimney.
If you want to cool down a drink with ice, which of the following would make it cool faster and why?
Crushing the lump into small pieces will put more of the ice’s surface area is in contact with the drink.
If you want to light some wood on fire, what would most likely make the wood light, and why?
Breaking the log down into small pieces of wood will increase the amount of wood surface that can catch fire.
Which of the following items would remain without rusting longer: a solid lump of steel, or steel wool that weighs the same amount?
The lump of steel would stay without rusting longer, because not as much of it comes in contact with the air.
