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OurCurseIsWorse
Oct 1, 2006, 06:31 AM
A dare devil is shot out of a cannon at 45 degress to the horizontal with an initial speed of 25 m/s. A net is positioned a horizontal distance of 50 m from the cannon.

A. At which height above the cannon should the net be placed in order to catch the daredevil?

B. At which velocity does the daredevil strike the net?

tkrussell
Oct 1, 2006, 06:36 AM
Here are the formulae used to calculate your questions, found at:

http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html


Acceleration

Acceleration is defined as the rate of change of velocity. Acceleration is inherently a vector quantity, and an object will have non-zero acceleration if its speed and/or direction is changing. The average acceleration is given by

where the small arrows indicate the vector quantities. The operation of subtracting the initial from the final velocity must be done by vector addition since they are inherently vectors.

The units for acceleration can be implied from the definition to be meters/second divided by seconds, usually written m/s2.

The instantaneous acceleration at any time may be obtained by taking the limit of the average acceleration as the time interval approaches zero. This is the derivative of the velocity with respect to time: