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Muruga210
Jan 19, 2014, 07:44 AM
Two objects thrown with same velocity 25 m/s one after the other. One was thrown at 65 degrees. If they intersect at a point, what is the angle for the second one.

Catsmine
Jan 19, 2014, 11:23 AM
65 degrees as well. They will intersect on the ground.

ebaines
Jan 19, 2014, 12:53 PM
I like Catsmine's answer - it's not bad assuming the two projectiles stick where they land. But if the intent is that the two projectiles intersect while in the air then the answer depends on the time interval between the throws - "one after the other" isn't specific enough.

Catsmine
Jan 19, 2014, 01:18 PM
Anything small and regular enough to be "thrown" at 54 mph (25m/s) will have considerable terminal velocity when intersecting the ground. Bouncing is improbable.

ebaines
Jan 20, 2014, 06:52 AM
Bouncing is improbable

I suggest you watch a baseball game, soccer match, or football game some time, all of which involve "projectiles" moving well in excess of 25 m/s that do indeed bounce when they hit the ground.

talaniman
Jan 20, 2014, 07:11 AM
The question was the angle of the second projectile to intersect with the first. I get <65 degrees. Intersecting at the downward slope of the first projectile. The variable being the time between the objects being thrown.

ebaines
Jan 20, 2014, 07:27 AM
I get <65 degrees. Intersecting at the downward slope of the first projectile.

Yes, clearly that's true, assuming the first projectile is thrown at 65 degrees. If an answer of "less than 65 degrees" is good enough for the OP's purposes then this does it. However note that the OP is not specific as to which object is thrown at 65 degrees - he only says that "one of them" is, so it could have been either the first or the second. If the second object is thrown at 65 then the first must have been thrown at an angle greater than 65 degrees. In either event as already noted if a more accurate answer is needed it will depend on the OP specifying the time interval between launches of the two objects. And again all this assumes that Catsmine's answer is not what the OP is looking for.