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High School Archive

Browse High School Physics/Chemistry

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Summing an Oscillating Series [08/10/1998]

Does 1 - 1 + 1 - 1 + 1 - ... equal 1 or 0

Surface Areas of Soap Bubbles [11/30/1999]

If you build a frame shaped like a tetrahedron and dip it in bubble solution, why do all of the faces of the bubble collapse to a point in the middle of the tetrahedron?

Throwing and Dropping Objects [11/26/2002]

Why, when you throw something in one direction and drop something at the same time, do they land on the ground at the same time? Also, when you throw something in the air, does it come down at the same pace as it went up?

Tides and Simple Harmonic Motion [08/11/1998]

After low tide, find the soonest that a vessel requiring a minimum water depth of 15m can pass through an inlet...

Time and Mean Velocity [01/16/2003]

Why is s = s0 + v0 t + 1/2 a t^2 true?

Torque of a Tree Limb or Pole [05/28/2008]

If I cut off the last 30% of a 500-pound tree limb, by how much have I reduced the force that is trying to tear the limb off the tree?

Traveling Trains and Nonlinear Systems [07/16/1998]

A train leaves town A and travels 540 miles at a uniform speed, followed an hour later by another train.... What were the speeds of the trains?

Travelling at Light Speed [04/11/1998]

How much time would it take to go to Mars or Jupiter at light speed?

Turning in Dance [5/30/1996]

I am interested in finding out how a dancer is able to sustain a turn. What roles do angular velocity and acceleration play?...

Two Cars [08/11/1999]

How long does it take car B to draw even with car A, and how far does car B travel?

Two Dogs Pulling a Sled [10/15/2001]

What are the magnitude and direction of the force the person will have to exert on the sled to keep it moving along the centerline of the road at constant velocity?

Two Masses Attached to a Spring [12/27/2000]

Two masses are attached to either end of a spring in a gravitational field. One mass is held fixed and the second mass is allowed to hang free and stretch the spring. When the upper mass is released, will the lower mass remain motionless until the spring is in its rest state?

Unit and Basis Vectors in Three Dimensions [05/09/1998]

Explanations and uses of unit vectors and basis vectors.

Using Imaginary Numbers [05/04/2001]

Where do we use imaginary numbers in the real world?

Using Vectors in Geometry and Physics [07/10/1998]

How do you use vectors in problems about medians, areas, and acceleration and velocity?

Vector Components, Magnitude, and Direction [07/23/1998]

Given the magnitude and direction of vectors M and M+N, find the components of N and the magnitude and direction of N.

Velocity and Time [02/11/1999]

A car averages 30 km/hr the first half of a trip, and 50 km/hr the second half of the trip. What is the car's average velocity for the trip?

Velocity of an Object in a Hurricane [4/5/1996]

I am doing my project on the distance an object is thrown by a hurricane...

Voltage Conversion Factors [01/10/2001]

What are the exact values of the constants for converting among peak, peak-to-peak, rms (root-mean-square) and average voltages?

Volume, Mass, Density [9/14/1996]

A flask that can hold 158g of water at 4 degrees Celsius can hold only 127g of ethyl alcohol. What is the density of ethyl alcohol?

Water Level in a Well [10/09/2001]

A man wishes to determine the water level in a deep well. He drops a stone into the well and hears it hit the water 3 seconds later...

Weight Change in a Moving Elevator [12/25/2003]

Why does a person weigh less when coming down the elevator than going up and more when going up than coming down? I think it's because of gravity, but what else is going on?

Weighted Average of the Velocities [01/30/2003]

Finding the average velocity for each of the three phases of the trip...

Weighted Coin Project [02/01/1997]

Analyze the results from flipping a non-weighted coin and a weighted coin.

Weight of a Gallon of Water [07/29/1999]

How much does a gallon of water weigh?

Weight of a Whale [05/24/1999]

How do you find the weight of a whale?

What Are Linear and Angular Velocity? [09/16/2004]

An introdution to the concepts of angular and linear velocity using a spinning CD as an example.

What is a Newton? [04/28/2002]

What is the weight in newtons of a 100-kg person?

What is Gravity? [05/06/2001]

Is gravity caused by the Earth's rotation, or do all objects exert a gravitational pull on each other?

Why Does Height Formula Use -16 Instead of -32? [01/31/2008]

If the acceleration of gravity is -32 ft/sec^2, why does the formula for the position of a falling object (h = -16t^2 + s) use -16 instead?

Why Don't Boats Sink? [10/15/2002]

I want to ask you about why ships don't sink.

Why Do We Have Leap Year ? [02/25/1998]

Why do we need to have one extra day each 4 years?

Why is the Universe Black? [04/11/2001]

If a black hole sucks everything into it, wouldn't space be void?

Why Not Meter to the Meter Power? [08/10/2001]

Why don't we encounter a quantity with dimensions such as m^s or m^m (meter to the power of meter)?

Why Take Averages in Experiments? [05/04/2003]

I have to measure the time it takes from when I release a toy car until it reaches the bottom of a 6-foot ramp.

Wile E. Coyote Lands in the River [08/20/1999]

Wile E. Coyote is standing on a springboard atop a high cliff. Road- runner drops a boulder on the other end of the springboard, sending Wile up at an initial velocity of 4 m/s. At what time will he land in the river, 120 m below the top cliff?

Will the Train Stop in Time? [09/21/1999]

The engineer of a train traveling at 80.0 m/s sees a car stalled on the tracks 2000 m ahead and immediately applies the brakes; the train slows down at the rate of 1.50 m/s squared...

Work and Energy Problem [5/14/1996]

The mass of a loaded helicopter is 1500kg. How much energy does its engine expend in ascending vertically for 120m?

Work Needed to Lift a Leaky Bucket [08/01/1999]

How can you calculate the amount of work needed to lift a bucket of water to the top of a well if there is a hole in the bucket causing water to leak out at a rate proportional to the height of the water in the bucket?

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