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16 items are filed under this topic.
An egg falls from rest 2018-05-10
From Amy:
An egg falls from rest a distance of 75cm to the floor. Neglecting air resistance, at what speed does it hit the floor?
Answered by Penny Nom.
An electron in a TV tube 2013-02-15
From anu:
an electron in a TV tube is beamed horizontally at a speed of (50^6) m/sec. towards the face of a tube 40 cm away about how far will the electron drop before it hits? no information has been provided of initial height from where it is beamed.
Answered by Robert Dawson.
Romeo throws a pebble at Juliet's wondow 2011-08-22
From Natalie:
There is a picture of Romeo trying to attract Juliet's attention without her nurse who is in a downstairs room, noticing. he stands 10m from the house and lobs a small pebble at her bedroom window (3.5m high). Romeo throws the pebble from a height of 1m with a speed of 11.5m/s at an angle of 60degrees to the horizontal. I have already found that it take 1.74seconds to reach the window and that it does in fact hit Juliet's window however i cannot work out the speed of the pebble when it hits the window! The answer is 9.12m/s but I cannot reach this answer. Hope you can help me :)
Answered by Robert Dawson.
Initial Velocity of a Car Plunging Off a Cliff 2009-06-07
From Mimi:
A car fails to take a sharp turn on a flat road and plunges off a cliff. The car lands 65m horizontally and 43m vertically from where it left the edge of the cliff. How fast was the car travelling?
Answered by Stephen La Rocque.
A Falling Rock 2008-07-11
From Rita:
This question has 3 parts. If a rock falls from a height of 20 meters on the planet Jupiter, its height H (in meters) after x seconds is about H(x) = 20 - 13x^2 (a) What is the height of the rock when x = 1.2 seconds? (b) When is the height of the rock 15 meters? (c) When does the rock strike the ground? Thank you
Answered by Janice Cotcher.
Constantly accelerated motion 2007-10-29
From Priyanka:
A, B and C are three points lying in that order on a straight line. A body is projected from B towards A with speed 3 m/s. The body experiences an acceleration of 1 m/s^2 towards C. If BC =20 m, find the time taken to reach C and the distance travelled by the body from the moment of projection until it reaches C.
Answered by Stephen La Rocque.
The range of a projectile 2007-09-18
From Claudette:
This is a maximum minimum problem that my textbook didn't even try to give an example of how to do it in the text itself. It just suddenly appears in the exercises. Problem: The range of a projectile is R = v^2 Sin 2x/g, where v is its initial velocity, g is the acceleration due to gravity and is a constant, and x is the firing angle. Find the angle that maximizes the projectile's range. The author gives no information other than the formula. I thought to find the derivative of the formula setting that to zero, but once I had done that, I still had nothing that addressed the author's question. Any help would be sincerely appreciated. Claudette
Answered by Stephen La Rocque.
Projectile motion equations 2007-06-12
From Dillon:
Ron throws a ball straight up with an initial speed of 60 feet per second from a height of 5 feet. Find parametric equations that describe the motion of the ball as a function of time. How long is the ball in the air? When is the ball at its maximum height? What is the maximum height of the ball?
Answered by Stephen La Rocque.
By how much is 100 multiplied or divided,... 2005-01-27
From Benedict:
By how much is 100 multiplied or divided, so that whether the number obtained is divided by 5 or 7, there will be a remainder of 1 and so that at the same time, the first quotient is greater by 4 than the second?
Answered by Penny Nom.
Typing a project 2001-05-01
From Tom:
Two students have to type a project. One can do it in 2 hours. It would take the other student three hours. They have 2 type writers. How fast can they finish by working simultaneously?
Answered by Claude Tardif.
The path of a cannonball 2001-01-15
From A student:
Artillerymen on a hillside are trying to hit a target behind a mountain on the other side of a river. Their cannon is at (x, y) = (3, 250) where x is in kilometers and y is in meters. The target is at (x, y) = (-2, 50). In order to avoid hitting the mountain on the other side of the river, the projectile from the cannon must go through the point (x, y) = (-1, 410).

Write the equation for the problem.

Answered by Penny Nom.
Projecting a line segment onto a plane 2000-06-08
From Monica:
What is the measure of the angle determined by a 14 inch segment and its projection into a plane if the length,in inches, of the projection into the plane is 7 inches?
Answered by Penny Nom.
A valentines project 2000-02-21
From Courtney Dohoney:
I was assigned a valentines project. Our job is to make a valentines card that has a math theme. On my valentines card I would like to include the set of equations that when graphed look like a heart. If you can figure out a set of equations and get it back to me I would be very happy.
Answered by Harley Weston.
The Jasper Project problem solving problem posting 1999-05-04
From Heidi Laura Bergman:
I am a pre-service teacher in my third semester (out of four) of student teaching at the University of Wisconsin - Madison. I am wondering if you can tell me anything about "The Jasper Project" or where I might be able to find out more information regarding this topic. Thanks, Heidi
Answered by Rick Seaman.
Non-Euclidean Geometry 1999-02-10
From Robert Smith:
Is non-euclidean geometry necessary for the college bound student? I have students that are inerested in teaching math one day. My school is restricted to Euclidean Geometry.
Answered by Walter Whiteley and Jack LeSage.
Projections quadratiques 2003-12-14
From Jennifer:
Je vous serais très reconnaissante si vous pouviez m'expliquer :
pourquoi la moyenne des projections quadratiques d'un segment sur un axe (en 3D) est égale à a*a/3 sachant que "a" représente la longueur de ce segment et que toutes les orientations du segment sont également probable.

Answered by Claude Tardif.



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