Excel in math and science
Master concepts by solving fun, challenging problems.
It's hard to learn from lectures and videos
Learn more effectively through short, interactive explorations.
Used and loved by over 7 million people
Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.
Excel in math and science
Master concepts by solving fun, challenging problems.
It's hard to learn from lectures and videos
Learn more effectively through short, interactive explorations.
Used and loved by over 7 million people
Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.
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A whale and a chihuahua dog are in free fall while skydiving on the moon (there is no air resistance).
Which animal has a greater acceleration?
Note: Don't worry about the whale and the chihuahua, they're skydiving with MoonJumps Inc. which supplies them with rocket packs for a safe landing.
by
Danielle Scarano
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In the figure below, the skier crouches in an 'egg position.'
Which of the following options best describes her effort to crouch like that?
by
Shreyansh Mukhopadhyay
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Each turquoise rectangle has dimensions of a×b.
What is (a+b)2−(a−b)2?
by
Andrew Hayes
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How many times in a day (00:00-24:00) do the minute and hour hands of an analog clock form a 180∘ angle, i.e. form a long, straight line?
by
Chandrashekar Giridharan
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In Germany, the problem to the right is known as "Das Haus vom Nikolaus." The left diagram is a "house" that can be drawn with a single stroke of a pen (never drawing the same segment twice). A possible solution is on its right.
Which of the diagrams below can be drawn with a single stroke of a pen?
by
Markus Michelmann
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