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High School Archive

Browse High School Physics/Chemistry

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Einstein [12/18/1997]

I am in fourth grade. Can you explain E = MC^2 in simple language?

Electrical Relationships [12/10/1996]

The resistance in an electrical circuit is related to the diameter of the wire and the length of the wire. How does resistance vary with diameter?

Electricity: Volts and Amps [10/18/2001]

How is electricity measured?

Energy Formula [10/02/2002]

What does e=mc^2 mean, and why?

Energy Transformation [02/13/2003]

Can you explain the formula for energy transformation on a roller coaster?

Escape Velocity [6/13/1996]

How did Einstein work out how fast you need to go to get off the earth?

Exact Numbers and Conversion Statements [07/25/2005]

I'm confused about how to decide if a number is exact or inexact. I know that in general measurements are considered inexact, but how about conversion factors such as 1 inch = 2.54 cm? The exactness of the number plays a role in the number of significant digits to keep. What other kinds of numbers are considered exact and inexact?

Exact Weight of One Gallon of Water [08/15/2001]

What is the exact weight of one gallon of water? The best answer I can get is 8.33 or 8.34, depending on the source I go to.

Examples of Cooling, Growth and Decay [06/03/1999]

Can you give some real life problems involving Newton's cooling method, logistic growth, and exponential growth and decay?

Expanding Water [03/12/1997]

Why does water expand when it freezes when other materials contract?

Explanation of Electrical Impedance [03/26/2004]

We had a speaker blow and I was told that it was because of the impedance. What does that mean?

Exponential Decay [06/09/2005]

Does an exponential decay calculation ever reach zero?

Extraneous Solutions [08/08/2003]

What should an engineer interpret from an equation, or the solutions of that equation, if its solutions prove to be extraneous?

Falling Chain [12/31/1997]

A chain 1 meter long is lying on a table with 25 cm. of it hanging in the air. It starts to fall without friction; how long will it fall?

Falling Football [1/11/1995]

If I were to drop a football off the top of Mile High Stadium, how long would it take for the football to hit the ground?

Falling through the Earth [12/31/2001]

If a hole is drilled through the center of the earth to the other side and you jump in, what will happen?

Falling Through the Earth [05/27/2002]

If someone dug a hole straight down all the way through the earth and then jumped into it, what would happen when he came out the other side?

The Feynman Double Slit [02/01/2002]

What is quantum mechanics?

Finding a Formula That Fits the Data [01/26/2000]

How can I find a formula that fits a chart of tensile strength data I've collected?

Finding the Highest Point [4/13/1996]

A ball is thrown into the air, and its height, h, at any time, t, in seconds is given by h = -16(t-1)^2 = 212...

Finding the Shape of a Funnel Curve [04/08/2001]

Find the equation of the curve of revolution of a coin leaving a chute.

Finding the Velocity of a Missile [12/10/1999]

If the angle of launch is 45 degrees and the distance to the target is 1000 m, what is the velocity of the missile?

Floating Copper Ball [02/26/2002]

Find the wall thickness of a hollow copper ball (sphere) with an outside radius of 50.0 cm that "just floats" in water.

Force = mass x acceleration (F = ma) [11/23/1996]

Find the magnitude of the earth's acceleration toward an apple.

Force of a Falling Object [12/27/2002]

If a 10-lb. bowling ball is dropped from 100 feet, how hard will it hit the ground?

Forces of Nature [10/9/1995]

How can a sliding incline rod fall sideways? Is there a force of motion I'm not taking into account?

Formula for Calculating Work [06/21/2005]

My calculus text defines the formula for work as W = Fd, so the work needed to lift a 500 lb beam 30 feet would be 500 * 30 = 1500 ft-lbs. But don't we really have to exert an upward force greater than 500 lbs in order to get the beam to move?

Formula for Gravity [9/2/1996]

If I throw a ball straight up in the air at 40 miles an hour, how long will it take for the ball to come down?

Formulas Regarding Radio Waves [11/17/2004]

Why does 2pi appear in many formulas involving high frequency radio transmissions and antennas?

Fourier Transforms [09/17/1998]

What is a Fourier Transform and what is it used for?

Fourier Transforms [10/19/2001]

I know what the sinc function is, but I can't convert my expression (in terms of sin) to an expression (in terms of sinc).

Fourier Transforms [04/20/1997]

What is the relation between Fourier transforms and Laplacian equations?

Free Fall [10/16/1997]

A ball with a mass of 0.5kg is dropped from a height of 190cm...

From What Height Did the Stone Fall? [01/30/2002]

A falling stone takes .30 seconds to travel past a window 2.2m tall. From what height above the top of the window did the stone fall?

A Function for Damped Simple Harmonic Motion [10/17/1998]

The end of a plastic ruler is vibrating in damped harmonic motion. Find an expression for the position of the end of the ruler.

Galilean Transformations [09/01/99]

Could you please explain to me the basic principles of Galilean transformation, and provide an example?

Gravitational Catch-Up [09/15/2003]

A stone is dropped from the top of a tower. One second later another stone is thrown vertically downwards from the same point with a velocity of 14 m/s. If they hit the ground together, find the height of the tower.

Gravity [11/1/1994]

When space ships get close to earth, gravity seems to affect the occupants really fast. Why isn't the effect of gravity a gradual occurrence? Does it have anything to do with that law about any two bodies in the universe affecting each other... and does it have to do with inverse relationships?

Gravity [05/07/1999]

Which ball will hit the ground first...?

Gravity [05/21/1999]

Why does any free-falling object fall at the rate of 9.8 metres/ second^2 despite its mass?

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