A myopic eye has a far point of 3m and a near point of 150mm . State the type of spectacle lens needed for viewing an object at normal far point and determine its power in dioptres . Find the near point when wearing this lens ?
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The thinkquest competition 2012 was held under three categories. The winners of the competition under each category is detailed below.
ThinkQuest Projects – 19 and Under
1st Place – 19 and Under – World Hunger
This team harnessed the full potential of the Internet to spread their message about food scarcity. They hope to inspire and encourage others to take part in ending starvation.
2nd Place – 19 and Under
Vish-Amrit: Transform Poisoned Water Into Nectar
When will displacement and velocity be negative ? Can you explain me about angular acceleration and angular velocity.
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The signs are conventional. We take one direction as positive and the direction opposite to it as negative.
When we discuss one-dimensional motion, it is easy to take the help of the number-line, whatever towards right is positive and towards left is negative. If the initial direction of motion is taken as positive and the further displacements does not make the body to go beyond the initial position in opposite direction, the displacement will be positive.
First and second place teams from the ThinkQuest International Competition will receive a trip to ThinkQuest Live for themselves, their coach, and one adult chaperone per student. ThinkQuest Live is a five day event hosted by the Oracle Education Foundation in the San Francisco Bay Area, California.
The event includes:
- Educational workshops and activities
- Social events
- Sightseeing excursions
- The elegant and magical ThinkQuest Awards Dinner
The competition was held under 3 categories –
- ThinkQuest Projects – Develop a website in ThinkQuest Projects.
- Digital Media – Produce an online journal/blog, a stand-alone website, photo essay, animation, public service announcement, video or some combination of these items.
- Application Development – Develop an interactive application or game.
The competition started on September 14, 2011 and the deadline for submitting entries was April 25, 2012 at 11:59:59 PM Pacific Daylight Time (PDT)
Today 20 June 2012 is the deadline for declaration of the names of winners.
In India students from Kendriya Vidyalayas and Navodaya Vidyalayas participated in the competition in mass.
See the winners of previous years and their work here at http://www.thinkquest.org/library/winners/2011_projects.html
Axions are hypothetical particles with a very low mass. According to Einstein, mass is directly related to energy, and therefore very little energy is required to produce axions. “The existence of axions is not proven, but it is considered to be quite likely,” says Daniel Grumiller.
In quantum physics, every particle is described as a wave. The wavelength corresponds to the particle’s energy. Heavy particles have small wavelengths, but the low-energy axions can have wavelengths of many kilometers.
Consider a disk rotating in a horizontal plane with a constant angular speed “omega” about its center O.
The disk has a shaded region on one side of the diameter and an unshaded region on the other side.
When disk is in horizontal plane x-y with left half shaded and right half unshaded, two pebbles P and Q are simultaneously projected at an angle towards R.
The velocity of projection is in the y-z plane and is same for both pebbles with respect to the disk.
(i) they land back on the disk before the disk has completed one-eighth rotation,
(ii) their range is less than half the disk radius,and
(iii)”omega” remains constant throughout.
Then where will the two pebbles land?
(All are invited to answer this)