Problem 1:

You are trying to win a prize at the state fair by knocking a massive can off a shelf. You have a choice of 4 different objects to throw at the can, each with a mass of 1 kg. With which of the following objects are you most likely to win?

Problem 2:

On a windless day, a pitcher throws a baseball toward home plate without any significant spin. After the ball has passed through the air, in which direction is the air moving on average?

Problem 3:

When a cylinder in an automobile's engine is going through the power stroke, the hot burned gas is pushing the piston out of the cylinder. As the piston moves out of the cylinder, the burned gas does work on the piston and

Problem 4:

To save the earth from an asteroid impact years in the future, engineers land an explosive on the asteroid and blow it to bits. Just before the detonation, the asteroid was heading directly toward mars and just after detonation, the largest piece of asteroid is heading directly toward the sun. Just after the detonation, the total momentum of all the asteroid pieces points

Problem 5:

An automobile's internal combustion engine burns a mixture of fuel and air in its cylinders. It is impossible for this engine to convert all of the chemical potential energy of the fuel and air mixture into mechanical work because burning that mixture increases its

Problem 6:

Your grandfather clock uses a pendulum as its timekeeper. At home, that clock keeps perfect time. When you move the clock to your dorm room, where the earth's gravity is slightly weaker than at home, the clock

Problem 7:

When wood burns in air, the water and carbon dioxide molecules that form as the result of combustion reactions have

Problem 8:

You are trying to set the world's record for drinking water through the tallest drinking straw. You only need to drink one drop of water, so speed doesn't matter. What could you do to have the best chance of setting this record?

Problem 9:

A volleyball falls onto the ocean, where it is affected by waves traveling on the ocean's surface. If a steady pattern of wave crests is heading north at 4 mph (4 miles per hour) on a windless day, how will the floating volleyball move as it encounters this wave pattern?

Problem 10:

Your glass of water has one cube of ice floating at the water's surface. Part of the cube is above the water. Olive oil is less dense than water. When you pour a layer of chilled olive oil onto the water's surface, the ice cube

Problem 11:

The characteristic of a harmonic oscillator that makes it especially suitable for use as a timekeeper in a clock is that

Problem 12:

You are swinging a bucket full of water around you in a big horizontal circle at a constant speed. You are at the center of its circular path. The net force on the bucket points directly

Problem 13:

You are flying a kite on a long string and the kite hovers motionless in the sky as the wind blows past it. The kite is high up to your east and you are pulling the kite string downward and westward. In which direction is the kite pushing on the air that passes it?

Problem 14:

You are using a hand-powered pump to add air to a bicycle tire. As you pump air quickly into the tire,

Problem 15:

Suppose it's a hot summer day, but the air in your room is much colder than the outdoor air. If you remove 1 J of thermal energy from the cold room air and add that 1 J of thermal energy to the hot outdoor air, without doing anything else at all, what happens to the total entropy (disorder) of world?

Problem 16:

You're eating lunch outdoors on a hot day and half the ice in your glass of water has melted since you started eating. How has the temperature of the water in your glass changed over that period?

Problem 17:

You are designing a chair for a museum. While your chair will be a work of art, it must also be practical and it mustn't tip over easily. To ensure that it stays upright, you design it so that its

Problem 18:

When water flows around a bend in a garden hose, the water pressure

Problem 19:

You watch from the ground as a crane lifts a large bucket of cement upward to a construction project. The bucket and cement are moving straight upward at constant velocity. As the crane's cable lifts the bucket, the cable is

Problem 20:

A rocket designed to put a satellite in orbit around the earth has two main tasks. First, it must lift the satellite above earth's atmosphere to eliminate air resistance. Second, it must

Problem 21:

You're drinking a cup of hot coffee in an airplane at 35,000 feet. Suddenly the airplane pressurization system fails and the cabin's air pressure decreases abruptly. The coffee begins to boil because its temperature

Problem 22:

An airplane is cruising at constant velocity, 30,000 feet in the air. Which of the following correctly describes the situation above the airplane's wing?

Problem 23:

Even though your Thanksgiving dinner consists of a tofu turkey, you discover that it contains a wishbone. You and your cousin decide to break the wishbone; the one with the large half gets their wish. Your cousin holds one end of the wishbone motionless as you pull the other end toward you rapidly. The wishbone snaps and you're left holding only a tiny fragment. Better luck next time! Breaking the wishbone required energy and that energy was provided by

Problem 24:

The chemical bond that causes two oxygen atoms to cling together as an oxygen molecules is

Problem 25:

Because of bad planning during the design and construction of a high-rise apartment building, all 50 floors of the building receive their water from a single pipe. That pipe is fed from a water tank located on the building's roof. On opening day, residents on various floors begin taking showers and have different experiences. They quickly discover that the total energy per liter in the spraying water is (neglecting any effects of viscosity and friction)

Problem 26:

Two identical rooms at identical temperatures contain identical collections of atoms. In one room that collection consists of moist air and an empty bowl and in the other room that collection consists of dry air and a bowl full of water. Which of the two rooms has the greater entropy (disorder)?

Problem 27:

Ice cubes gradually shrink in a frost-free freezer because

Problem 28:

Which of the following is a harmonic oscillator?

Problem 29:

A silver flute produces a tone as the flautist blows across a hole near the end of the flute. What is vibrating to produce this tone?

Problem 30:

You add a teaspoon of salt to a glass of pure water. The salt initially sits at the bottom of the water, but it slowly dissolves so that eventually you have a glass of salt water. Which has more entropy: the glass of pure water with salt sitting at its bottom or the glass of salt water?

Problem 31:

You wake up one very cold winter morning to find the grass outside covered with frost. How did this ice form on the grass?

Problem 32:

The ocean tides are caused primarily by

Problem 33:

You are visiting a playground and you notice that a girl on one swing completes each full cycle of motion in much less time than a boy on another swing. The girl has a much shorter period of motion (time between cycles) than the boy because

Problem 34:

Two toy cars roll off a level table side-by-side at the same time and in the same direction. The cars soon hit the level floor below the table. The cars have identical weights, but the violet car was traveling twice as fast as the yellow car when they left the table. In this situation,

Problem 35:

Compared to an ordinary surface wave on the ocean, a tsunami has a much longer wavelength and therefore

Problem 36:

The first kind of perpetual motion machine provides an inexhaustible supply of mechanical work (or the equivalent of work), but consumes nothing at all from its environment, not even heat. An example would be a black box that consumes nothing yet provides electricity forever. This form of perpetual motion machine is impossible because it

Problem 37:

It's just below freezing outside and your walkway has a layer of slippery ice on it. Which of the following substances will cause that ice to melt if you sprinkle it on the ice?

Problem 38:

When a liquid flows through a collection of stationary obstacles, its flow can be smooth and laminar, or it can be swirling and turbulent. The liquid's flow is more likely to become turbulent if you increase its

Problem 39:

You are eating at an outdoor restaurant on a cold day and the restaurant has a red hot heating element positioned about 10 feet above you that keeps you surprisingly warm. Heat from that element reaches you

Problem 40:

The airflow around a dust particle is laminar. What force prevents that dust particle from falling rapidly to the ground and keeps it aloft for a long time?

Problem 41:

On a hot, humid day, the liquid perspiration on your wet skin doesn't do a very good job of cooling you off. The weather changes and the air suddenly becomes less humid, although its temperature remains the same. You find that you're cooling off better because water molecules now

Problem 42:

You forgot to tip the bartender who brought a Shirley Temple drink to your luxury hotel suite. So you're leaning out over the balcony of your 20th floor suite and dropping solid gold marbles into the tip jar on the ground floor patio bar. You notice that it takes 4 seconds for each marble to fall into the jar, 20 floors below. When each marble has fallen for only 2 seconds, which floor of the hotel is it nearest? [Note: neglect any effects due to the air.]

Problem 43:

If you're designing an energy efficient automobile, why should you minimize the diameter of the turbulent wake it leaves behind in the air?

Problem 44:

You are riding a rollercoaster with a loop-the-loop. You have just rolled up the side of the loop and are, at this moment, exactly at the top of the loop. You and the car are upside down, yet you are pressed tightly into your seat. At this moment, you are accelerating

Problem 45:

Increasing the amount of carbon dioxide (a greenhouse gas) in the earth's atmosphere

Problem 46:

You place balls of cookie dough on a shiny metal cookie sheet and pop the sheet into the oven. The oven is being heated by an electric heating element at the bottom of the oven. How does heat flow from the heating element to the cookies?

Problem 47:

As water flows downward in a vertical pipe that has a uniform diameter, the water's gravitational potential energy decreases,

Problem 48:

Ice cannot be colder than

Problem 49:

When smokejumpers parachute into forest fires, they have with them emergency tents made of shiny aluminum foil. If they're caught in the blaze, they lie flat on the dirt in a low spot with the aluminum tent propped just above them. If the fire passes quickly enough, they have a good chance of surviving it. The tent is made of aluminum because

Problem 50:

You are waterskiing at constant velocity on a calm lake while wearing a lifejacket. As you move across the water, you are doing

Problem 51:

Two guitar strings have the same tension and the same length, but one string is more massive than the other. When you pluck them both simultaneously, how do the fundamental pitches (frequencies) of the two strings compare?

Problem 52:

An airplane is cruising horizontally at 30,000 feet and is traveling at constant velocity. The overall force that airplane exerts on the air points

Problem 53:

Your winter jacket contains 8 ounces of goose down insulation, just enough to completely fill the interior of the jacket. Suppose you open the seams and tightly pack 8 more ounces of goose down insulation into the jacket. After sewing up the seams, your jacket will be

Problem 54:

You are waterskiing at constant velocity behind a powerful speedboat and your arms and legs are getting tired. The net force acting on you

Problem 55:

The second kind of perpetual motion machine provides an inexhaustible supply of mechanical work (or the equivalent of work), but consumes only heat from its constant-temperature environment. An example would be a black box that absorbs heat from the 70 °F room air and converts that heat into electricity forever. This form of perpetual motion machine is impossible because it

Problem 56:

If you're trying to increase the pressure in the water distribution system by modifying the local water tower, you should make the water tower

Problem 57:

Near sea level, water normally boils at about 212 °F (100 °C). However, a microwave oven can heat water in a glass container above that temperature if

Problem 58:

A huge abstract iron sculpture has been installed in front of the local art museum. It sits there motionless, "guarding" the main doorway. The sculpture is experiencing two forces: its weight downward and a force upward from the brick courtyard beneath it. We know that these two forces on the sculpture are equal in amount but oppositely directed because

Problem 59:

To win a stuffed animal at the state fair, you simply need to drop a glass marble onto a stationary glass plate and have the marble come to rest on that plate. Unfortunately, when the marble hits the plate, it bounces upward because the marble

Problem 60:

Once a baseball leaves the pitcher's hand and is heading toward home plate, it gradually slows down. The primary reason for this slowing is that the air pressure