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	The flight of a football		2020-05-06
		Michael pose la question : Football is thrown from a 10-yard line. It reaches its highest height of 20 yards. It lands on the 50-yard line after 2 seconds. What is the equation of the parabola that models this throw? I really need help as I've been on this for the longest amount of time. Penny Nom lui répond.
	The inverse square law		2018-06-05
		Amy pose la question : Question about inverse square law ; Hi, I'm trying to understand some nuances about this law and have been reading about it a lot online and trying out some homework for personal interest (hobby ) - not school related. I understand that the simple formula is ; 1/d^2 I was wondering about what appears to be an oddity to me, that I came across when I was working with a test example I found at this link ; http://www.softschools.com/formulas/physics/inverse_square_law_formula/82/ The problem that caught my interest was this one on that page ; "1) If a bright flashlight has a light intensity of 15.0 candela at a distance 1.00 m from the lens, what is the intensity of the flashlight 100.0 m from the lens?" So I have a few different questions about this, but the most important one is, what does it mean if we replace the "1" in ; 1/d^2 with a different value such as a ratio in the form of a decimal value, so instead we have something like this ; 0.75/d^2 ??? Does this ratio represent a curve then? I am thinking that the "1" in the normal formula represents a straight line Some of the links I was researching ; http://wisptools.net/book.php?c=3&s=2 http://www.softschools.com/formulas/physics/inverse_square_law_formula/82/ https://www.nde-ed.org/GeneralResources/Formula/RTFormula/InverseSquare/InverseSquareLaw.htm Penny Nom lui répond.
	A ship and a light		2016-08-11
		Kirby pose la question : A ship is sailing due west when a light is observed with heading 297°50' from the ship. After the ship has travelled 2250 feet, the light heads 311°55' from the ship. If the course is continued, how close will the ship approach the light? Penny Nom lui répond.
	Travelling in a spacecraft		2016-03-25
		julie pose la question : if i was travelling in a spacecraft at the speed of light and i turned on my headlight would i see the beam ? Robert Dawson lui répond.
	A 5-person golf flight		2014-05-05
		Jeremy pose la question : can you have a 5-person golf flight and play only 3 matches so that one person plays one match each? Victoria West lui répond.
	Golf League Schedule for 15 weeks and three flights		2014-04-21
		bigdog pose la question : I need help setting up a 12 team (3 flights with 3 teams in each flight) 15 week league play schedule. Each team must play teams in there perspective flight twice during the 15 week season. Victoria West lui répond.
	Find the rate at which the searchlight rotates		2011-04-17
		Meredith pose la question : A searchlight is position 10 meters from a sidewalk. A person is walking along the sidewalk at a constant speed of 2 meters per second. The searchlight rotates so that it shines on the person. Find the rate at which the searchlight rotates when the person is 25 meters from the searchlight. Penny Nom lui répond.
	Trigonometry and picture hanging		2010-01-13
		george pose la question : The top of a picture 1m high 0.8m from the ceiling. At a point on the ceiling directly in front of the picture, we wish to install a light so that the angle subtended by the picture equals to the angle of depression of the top of the picture. How far out from the wall should the light be installed? Penny Nom lui répond.
	e = m c^2		2009-12-09
		Jim pose la question : Please explain the following formula: E=MC2 (squared) Robert Dawson lui répond.
	Two ships and a lighthouse		2009-05-27
		Chelsey pose la question : I have a question in regards to how do I know when to use tangent or cosine when determining angles. The question is: Looking north from the observation deck of a lighthouse 60 m above the sea, a lighthouse keeper sees two ships. The angles of depression to the ships is 5 degrees and 10 degrees. How far apart are the ships? I don't understand which one to use when solving the equation. Harley Weston lui répond.
	The number of hours of daylight		2008-06-03
		Marilyn pose la question : Hi, could you please help me with this question? In a city (in the Northern Hemisphere) the minimum number of hours of daylight is 9.6 and the maximum number is 14.4. If the 80th day of the year (March 21) has 12 hours of daylight, determine a sine function which gives the number of hours of daylight for any given day of the year. (Jan 1 = 1, Jan 2 = 2, etc). Thank you! Harley Weston lui répond.
	Light years to miles		2008-03-24
		Robert pose la question : HOW MANY MILES ARE THERE IN 7.5 BILLION LIGHT YEARS. Penny Nom lui répond.
	Related Rates (streetlamp and shadow)		2007-11-09
		Casey pose la question : A street light is mounted at the top of a 15ft pole. A man 6ft tall walks away from the pole at a rate of 5ft per second. How fast is the tip of his shadow moving when he is 40ft from the pole? Stephen La Rocque and Penny Nom lui répond.
	The distance of the Andromeda Galaxy		2007-10-22
		ROLY pose la question : What is 2.5 million miles x 6 trillion miles (light year) This is the distance of the ANDROMEDA Galaxy. Stephen La Rocque lui répond.
	Probability		2007-05-07
		Danielle pose la question : A box contains 3 defective lights and 5 non-defective lights. The lights are tested one at a time without replacement. What is the probability that the 3 defective bulbs will be found in the first 3 tests? is it 1/56 by chance? Stephen La Rocque lui répond.
	What is the intensity 5m below the surface?		2007-03-31
		david pose la question : I have this question which I am supposed to set it up and solve as a differential equation. I know how to solve the diffrential equation but I am having hard time understanding this question. Here is the question: The intensity of light in the ocean decreases the deeper you dive. In fact, the rate at which the intensity decreases is proportional to the current intensity. Setup the corresponding differential equation and solve for I(Y), the intensity I as a function of current intensity Y. If the light intensity 2m below the surface is 25% of the intensity at the surface, what is the intensity 5m below the surface. Can you please explain to me what does it mean by current intensity and how do I set this equation up. Thanks for the help. Penny Nom lui répond.
	A beam on a lighthouse		2007-03-28
		Lisa pose la question : A beam on a lighthouse 2000 metres away from the nearest point P on a straight shoreline revolves at the rate of 10 pi radians per minute. How fast is the beam of the light moving along the shoreline when it is 500 metres from P? Stephen La Rocque lui répond.
	How far from Earth is Neptune?		2006-03-21
		Scott pose la question : A laser beam travelling at the speed of light bounces off the planet Neptune and returns to Earth in 29 960.72 s. The speed of light is 299 792.5 km/s. How far from Earth is Neptune? Penny lui répond.
	What is 2,500 X 6 trillion miles?		2005-09-15
		Roly pose la question : ANDROMEDA Galaxy is 2,500 light years away. A light year is 6 trillion miles. What is 2,500 X 6 trillion miles in a mathematical number? Penny Nom lui répond.
	A lighthouse is located on a small island,...		2005-07-14
		Brittnee pose la question : A lighthouse is located on a small island, 3 km away from the nearest point P on a straight shoreline, and its light makes four revolutions per minute. How fast is the beam of light moving along the shoreline when it is 1 km from P? Penny Nom lui répond.
	Accelerating to the speed of light		2004-09-30
		Lars pose la question : How long time would it take to accelerate up to the speed of light with an acceleration speed similar to 0-100 seconds in 5 seconds? Penny Nom lui répond.
	A spotlight shines on a wall		2002-05-25
		Barb pose la question : A spotlight on the ground shines on a wall 12m away. If a man 2m tall walks from the spotlight toward the bldg at a speed of 1.6 m/s, how fast is his shadow on the bldg decreasing when he is 4m from the bldg? Penny Nom lui répond.
	Oven lights		2002-05-06
		Manny pose la question : Q.A manufacturer of stoves has to buy oven lights from from two diffrent companies because one company alone cannot meet its demand. the manufacturer purchases 60% of the oven lighs from comany A and the rest form Company B. Past experiecnce shown that 1% of Company A's oven are defective oven and 2.5% of Company B's oven light are defective. Determine the probability that a defective oven light is supplied by company A. Andrei Volodin lui répond.
	A lighthouse and related rates		2001-11-29
		Melissa pose la question : A lighthouse is located on a small island 3 km away from the nearest point P on a straight shoreline, and its light makes 4 revolutions per minute. How fast is the beam of light moving along the shoreline when it is 1 km from P? Penny Nom lui répond.
	A clap of thunder		2001-11-15
		Frustrated Mom pose la question : While getting a recipe for the Thanksgiving feast. The teacher was talking on the phone with a friend who lives four miles north of her. She saw a flash of lightning through the window: fifteen seconds later, she heard a clap of thunder. Ten seconds after that she heard the thunder over the phone. Where did the lightning strike in relation to the teacher's house. (There are two possible answers. Sound travels about 1/5 mile per second. Some people say it's not good to be on the phone in a thunderstorm). Claude Tardif and Penny Nom lui répond.
	A lighthouse problem		2001-11-02
		A student pose la question : A lighthouse at apoint P is 3 miles offshore from the nearest point O of a straight beach. A store is located 5 miles down the beach from O. The lighthouse keeper can row at 4 mph and walk at 3.25 mph. a)How far doen the beach from O should the lighthouse keeper land in order to minimize the time from the lighthouse to the store? b)What is the minimum rowing speed the makes it faster to row all the way? Harley Weston lui répond.
	Height of the lamp		2000-12-31
		Joey pose la question : The figure shows a lamp located three units to the right of the y-axis and a shadow created by the elliptical region x2 + 4y2 < 5. If the point (-5,0) is on the edge of the shadow, how far above the x-axis is the lamp located? Harley Weston lui répond.
	The speed of light		2000-06-19
		Benny Lau pose la question : I have a personal questions. In physics,if a person is running on a train, his relative speed on the ground will be the addition of the speed of train and the person. If u have a train inside another train and inside another train, so on...... can u reach the speed of light? It would need a very long distance. But if we make all the train travel in circles. Then we don't need that much distance. So can we achieve the speed of Light? Robert Coleman and Harley Weston lui répond.

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