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Measuring the Volume of My Body [09/17/2003]

How can I measure the amount of water that I displace, without having a second person to mark the levels of water in a tub or pool after I'm submerged?

Mixing Coffee and Milk: Ph and Buffers [07/10/2003]

If I mix coffee (pH 5) and milk (pH 6.9) (50%/50%), what will be the pH of the coffee/milk mixture?

Mixing Copper-Silver Alloys [06/09/1999]

How much of each type of two copper-silver alloys is needed to produce 1.2 kg of alloy containing 62% pure silver?

Molar Heat Capacity of a Gas [11/17/1999]

If the volume of n moles of a monatomic perfect gas with an initial volume V and an initial temperature T is halved at a constant rate while its temperature is doubled at a constant rate, how can I prove that the work done to the gas is given by W = nRT*(3*log[2]-1)?

Moment of Inertia of a Solid Cone [02/03/1999]

Find the Moment of Inertia of a solid cone in terms of its height and base.

Monkey Climbing a Chain [09/22/1999]

A 20-lb. monkey is attached to a 50-ft. chain that weighs 0.5 lb. per (linear) foot...

Monte Carlo Method and Computer Simulation [04/04/2002]

What is the Monte Carlo method? I know it's for estimating probability, but what is the point of it?

Motion and Force [11/28/2004]

You are a 50 pound person riding in a bus going 45 MPH, when the driver suddenly stops. If you were to 'fly' out of your seat, with how many pounds of force would you hit the windshield?

Motion of a Particle [3/31/1996]

I'd like to know how to solve a problem in which a particle is shot from the ground at an initial known angle and velocity. The force of friction is f=av^3 where {a} is a constant.

Motion Under Gravity [07/18/2003]

Use the equation s = -16t^2 + vt to determine when the height of an object is 960 feet if the initial velocity is 272 feet per second.

Motorcycle in the Air [1/4/1995]

When a motorcycle is in the air, why does pushing on the gas make it go up and braking make it go down?

Muzzle Speed [03/21/2002]

A 15-gram bullet strikes and becomes embedded in a 1.10 kg block of wood placed on a horizontal surface just in front of the gun. If the coefficient of friction between the block and the surface is .25 and the impact drives the block 9.5 meters before it comes to rest, what was the muzzle speed of the bullet?

Negative Entropy in Chemical Reactions [08/20/2001]

Could you name some chemical reactions in which the disorder of the chemicals involved decreases as a result of the reaction?

Newton's Law of Cooling [05/06/2003]

How long before the student arrived on the scene did the professor die?

Newton's Laws Applied to an Accelerating Car [05/26/2005]

When a car accelerates, what forces are involved? I'm curious both about the car itself and the forces experienced by a person sitting in the car as they are pushed back against the seat with acceleration and pushed against their seat belt when the car slows. What's going on there in terms of physics?

Newton's Third Law of Motion [05/08/2008]

Newton's third law says that when you exert a force on an object, the object exerts an equal and opposite force back on you. If that's true, how can I push something and have it move? Wouldn't the forces cancel out and the object stay at rest?

Ohm's Law and Battery Life [08/18/1999]

Given a 12V battery with 275 cold-cranking amps and a load of 12V at 7.2 A on it, how long should that battery run the load?

One equals Two [07/25/2001]

There is an algebraic manipulation involving division by zero that results in one equals two, or some other contradiction. What is it?

Over the Right Field Fence [04/11/1998]

What would be the distance of a hit from home base over the top of a 30 ft. high right field fence?

Parallel and Series-Parallel Resistance [05/24/2000]

How do you find the total resistance of resistors in parallel or in series-parallel?

Parsec (pc) [10/26/2001]

One of the unit conversions my Casio fx-991MS calculator does is pc to km and km to pc. What does "pc" mean in this context?

Percentage of Alcohol in a Solution [06/02/1999]

How do I find the percentage of alcohol in 30 liters of a solution that is mixed with 5 liters of a 90% alcohol solution?

pH Definition [10/20/2001]

What is the 'p' in pH?

pH Value [09/05/2001]

I would like to know the pH value of 0.1 N Sulphuric acid.

Physics - Acceleration [09/13/2001]

What equation do you use to find the time element when you have the change in velocity and the displacement?

Physics and a Balloon in a Car [06/09/2005]

Consider a balloon filled with helium, hanging from the floor of a car. The car is sealed, and is full of air at ambient surface pressure. If the car undergoes constant acceleration forwards only, which way, relative to the car, will the balloon move?

Physics: Collisions [12/17/1998]

Given the conditions of a collision, find the velocity of one element after collision.

The Physics of a Horse Pulling a Carriage [07/13/2005]

I'm trying to understand how Newton's Law works with regard to the forces that allow a horse to pull a carriage. How does that work?

The Physics of Baseball [07/11/2000]

How does a baseball move when it is pitched?

Plane Flying Parametrically [06/28/1999]

How can I find out when a plane, whose position approaching an airport is described parametrically by P_t = (1000,500,900)+ t[-100,-50,-90], will be closest to the traffic control center, located at (24,11,13)?

Projectile Dynamics [10/21/2000]

A particle is projected with initial velocity v and angle theta in a parabolic path. How can I show that at time t, when the angle to the horizontal is gamma, tan(gamma) = tan(theta) - (gt/v) sec(theta)?

Projectile Motion [02/27/2001]

If a cannon is firing a cannonball with an initial upward velocity of 100 feet per second, how do you set up a quadratic equation for the projectile motion of the cannonball?

Proof of E = mc^2? [05/04/2001]

I'm looking for a mathematical proof of E = mc^2. Can you help me fill in the gaps in my proof?

Proportionality and Absolute Temperature [06/06/1999]

If a gas occupies 100 liters at -13C, what is its volume at 26C? Why do I need to convert the temperatures to Kelvin?

Proportions for a Chemical Solution [6/24/1996]

I need to mix up a 10 percent solution that contains a dry chemical...

Purpose of Integrals [4/13/1996]

I am studing calculus, but the book I am using does not say what integrals are used for, or what their purpose is.

Quadratics in the Real World [07/30/1998]

Do you have any real world examples of uses of quadratics? For example, how are parabolas used?

Questions About Math [07/31/1999]

Why was the Cartesian plane invented? Were the more abstract branches of math developed just for fun? What is chaos theory? Why isn't Einstein's equation e = mc^3?

Radioactive Decay [10/26/2004]

The half-life of a radioactive element is 131 days, but your sample will not be useful to you after 90% of the radioactive nuclei originally present have disintegrated. For about how many days can you use the sample?

Radioactive Decay of an Isotope [01/05/1998]

I know the decay of the 226Ra isotope involves the use of logarithms (an exponential function ae^x), but I'm having trouble fitting my information to my equation...

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