6,899,043 research outputs found
Optimum take-off angle in the long jump
In this study, we found that the optimum take-off angle for a long jumper may be predicted by combining the equation for the range of a projectile in free flight with the measured relations between take-off speed, take-off height and take-off angle for the athlete. The prediction method was evaluated using video measurements of three experienced male long jumpers who performed maximum-effort jumps over a wide range of take-off angles. To produce low take-off angles the athletes used a long and fast run-up, whereas higher take-off angles were produced using a progressively shorter and slower run-up. For all three athletes, the take-off speed decreased and the take-off height increased as the athlete jumped with a higher take-off angle. The calculated optimum take-off angles were in good agreement with the athletes' competition take-off angles
Finding passwords by random walks: How long does it take?
We compare an efficiency of a deterministic "lawnmower" and random search
strategies for finding a prescribed sequence of letters (a password) of length
M in which all letters are taken from the same Q-ary alphabet. We show that at
best a random search takes two times longer than a "lawnmower" search.Comment: To appear in J. Phys. A, special issue on "Random Search Problem:
Trends and Perspectives", eds.: MEG da Luz, E Raposo, GM Viswanathan and A
Grosber
Optimum take-off angle in the standing long jump
The aim of this study was to identify and explain the optimum projection angle that maximises the distance achieved in a standing long jump. Five physically active males performed maximum-effort jumps over a wide range of take-off angles, and the jumps were recorded and analysed using a 2-D video analysis procedure. The total jump distance achieved was considered as the sum of three component distances (take-off, flight, and landing), and the dependence of each component distance on the take-off angle was systematically investigated. The flight distance was strongly affected by a decrease in the jumper’s take-off speed with increasing take-off angle, and the take-off distance and landing distance steadily decreased with increasing take-off angle due to changes in the jumper’s body configuration. The optimum take-off angle for the jumper was the angle at which the three component distances combined to produce the greatest jump distance. Although the calculated optimum take-off angles (19–27º) were lower than the jumpers’ preferred take-off angles (31–39º), the loss in jump distance through using a sub-optimum take-off angle was relatively small
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Long Night Against Procrastination: A Collaborative Take On An International Event
The Long Night Against Procrastination is an international tutoring event created by the writing center at the European University Viadrina in Frankfurt (Oder), Germany in 2010 (“Lange Nacht Der Aufgeschobenen Hausarbeiten”). The inaugural event was established by writing center staff in response to student requests for all-night tutoring support. Where lesser individuals would have chuckled in response to such a request, the writing center at European University Viadrina decided to give it a try. Writing center staff dubbed this event the Long Night Against Procrastination, or rather the Lange Nacht Der Aufgeschobenen Hausarbeiten, in German. This annual event has gained recognition and grown, spreading to writing centers at institutions such as DePaul University, University of Manitoba, and the University of Wisconsin-Madison. Naturally, the name of the event has been adjusted in response; the event is now Weltweit (or International) Long Night Against Procrastination.University Writing Cente
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