Problem 1:

You are on a 3rd floor hotel balcony, 10 meters above the bar. You lower a long straw into a pitcher of diet soda (essentially pure water) and find that you can just barely suck the soda up to your mouth. You move the straw over to pitcher filled with full-calorie soda (essentially sugar water, with a density that is 10% more than pure water). Now what happens when you begin sucking?

Problem 2:

A satellite is traveling around the earth in a circular orbit. It briefly fires its rocket engine to increase its speed in the forward direction; it is suddenly going faster but its direction of travel didn't change. As a result of this speed increase, the orbiting satellite's average distance from the center of the earth

Problem 3:

On a cold morning, you seal your empty plastic water bottle and thus trap the air inside it. Later in the day, the bottle and its contents are much warmer and the sides of the bottle are now bowed outward. As a result of these changes, the air pressure inside the bottle has

Problem 4:

As water in steady state flows straight down in a vertical pipe with a uniform diameter, that water transforms its

Problem 5:

A hydrogen-filled dirigible (a huge blimp or elongated balloon) floats in air because the hydrogen-filled dirigible contains

Problem 6:

As part of your new circus routine, you jump off a high platform onto a trampoline. You bounce up and down spectacularly before eventually settling at equilibrium on the trampoline. When during your descent from the high platform do you first stop accelerating downward?

Problem 7:

Water is flowing at constant velocity through a straight horizontal pipe. It is experiencing two forces: a forward force due to a difference in pressure at the two ends of the pipe and a backward force due to the water's viscosity and friction with the stationary pipe. How do the amounts of those two forces compare?

Problem 8:

You are drying your hair and you have put a diffuser (an anti-nozzle) on the end of the dryer. As it goes through the diffuser, the air slows down and its

Problem 9:

You're standing on the middle of the Ruffner Hall/Bavaro Hall pedestrian bridge when a group of prospective students jumps up and down and sets the bridge bouncing. As you bounce up and down about equilibrium, your speed is greatest when you are

Problem 10:

A block of wood is floating easily on the surface of a lake. The sun comes out and warms the air above the lake. The warming air's density decreases and the block of wood

Problem 11:

When you drop a beanbag on cement, the bag doesn't bounce. Suppose you are playing tennis with a beanbag instead of a tennis ball. How should you adjust your tennis racket to make the beanbag travel as fast as possible after you hit it with the racket?

Problem 12:

Your bottle of oil and vinegar salad dressing has separated, so that the oil is floating on the vinegar. You notice that a large herb is floating motionless at the interface between the oil and the vinegar. That herb's average density is

Problem 13:

The body of your car is supported by springs. When you put a 100-pound box of books into the trunk, the body's average height above the ground decreases by 1 inch. If you add a second 100-pound box of books to the trunk, the body's average height above the ground will decrease by an additional

Problem 14:

When you launch a toy water rocket, compressed air inside the rocket pushes water out of the rocket's tail as "exhaust" and the rocket blasts forward at high speed. Normally, you fill the rocket's hollow shell half-full with water and half-full with compressed air. Eliminating the water would allow you to put twice as much compressed air in the rocket and would double the rocket's stored energy. However, the air-filled rocket will barely move forward when you launch it because its air exhaust

Problem 15:

You are watering the garden with a hose and nozzle. You are holding the nozzle horizontally in order to spray a distant flower. As the water flows through that nozzle, it converts

Problem 16:

An apple sits motionless on a table. The amount of momentum that apple is transferring to the table each second is

Problem 17:

The maximum speed of a rocket-propelled spaceship with an exhaust speed of 5000 mph is

Problem 18:

To win a prize at the fair, you must toss a basketball into a stiff fruit basket and have the ball remain in that basket. The basket is tipped toward you and nailed to the wall. Its lower lip has just enough uphill slope to keep a stationary ball from rolling out. Each time you throw the ball into the basket, the ball bounces and rolls onto the floor. The conserved quantity that the basketball is unable to get rid of in order to stay in the basket is

Problem 19:

When you ride a bicycle, the ground exerts an upward support force on the wheel. When you turn the bicycle, the ground also exerts a horizontal frictional force on the wheel. Leaning the bicycle toward the inside of a turn keeps you from tipping over because the overall force that the ground exerts on the wheel (the sum of the support force and the frictional force)

Problem 20:

You are at a barbeque and the bottle of hot sauce is almost empty. You put the cap on the bottle and swing it rapidly in a circle with its cap end pointing outward. The remaining sauce collects just inside the cap and you are able to extract enough to spice up your vegiburger. This technique works because

Problem 21:

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 22:

You're at the lake and watch two children jump off a dock at the same time. They both kick equally hard during their jumps, but one child jumps mostly upward while the other child jumps mostly forward. After they leave the dock,

Problem 23:

Firefighters are battling a fire on the 10th floor of an apartment building. When they stand on the ground, their fire hose can only shoot the water up to the 8th floor. So they carry the end of the same fire hose up a 2-story-tall ladder and shoot water upward. Now the water rises to the

Problem 24:

You are floating along in a hot air balloon. You look up and notice that the bottom of the balloon is open. Apart from a few molecules that diffuse out, hot air remains inside the balloon despite this opening because

Problem 25:

You are riding on a playground swing. As you swing forward, there is a moment when you are directly below the pivot that supports the swing. At that moment, your speed is momentarily constant and you are

Problem 26:

You are bicycling at constant velocity along a horizontal road and you are wearing a backpack. As you bicycle, you are doing

Problem 27:

You drive too fast over a small hill and your car's wheels lose contact with the road. While your car is not touching the road, you are

Problem 28:

You're filming a movie and you arrange for two unoccupied cars to drive horizontally off a tall cliff. The Mercedes sedan weighs twice as much as the Mini Cooper, but the Mini Cooper is traveling at twice the velocity of the Mercedes when the two cars careen off the cliff side-by-side. In this situation, the two cars hit the level ground below the cliff

Problem 29:

A bicycle is remarkably stable while it's moving forward because, when you start to tip over,

Problem 30:

You roll a baseball off the top of a tall building and it hits the ground 4 seconds later. When the baseball has fallen for only 2 seconds, how far is it above the ground? [Note: neglect any effects due to the air.]