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Old 10-01-2006, 07:55 AM   #5 (permalink)
KnifeMissile
 
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Location: Waterloo, Ontario
Quote:
Originally Posted by soccerchamp76
1) Don't confuse speed with velocity.

2) Is this a calculus-based physics course or algebra-based?

Here are some of my thoughts:

At t=2, the y-component of speed will be zero. The x-component of speed does NOT change during the course of the flight. You can figure out the y-component using the acceleration due to gravity of two seconds (2 seconds to reach the top, two seconds to fall gives you two seconds of the y-component of speed).

For the height and distance (range) problems, you are going to need the angle at which the projectile was shot. Without the angle, you cannot solve the problem.
This is not true. All the information you need to solve the problem is given...

You can determine the maximum height because you know that the y component reaches the maximum height in 2 seconds. This is the equivalent of finding the distance an object travels after accelerating at 1G for 2 seconds...

You can determine the distance of the projectile because you know the time of flight, 2 + 2 = 4 seconds, and you know it's x component velocity, 10 m/s. This works out to 40m.

As you can see, the angle was not needed, here...

PS. I'm sorry I got to this thread so late. This forum is too slow to check too often...
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