Thursday

April 17, 2014

April 17, 2014

Posted by **abebe** on Friday, June 15, 2012 at 11:45am.

- physics -
**Elena**, Friday, June 15, 2012 at 5:02pmWithout air RESISTANCE(!), the horizontal component of the velocity is constant

v(x) =v(ox) = v•cos30 = 20•cos30 = 17.32 m/s.

The path of the projectile is symmetrical respectively the max height, therefore , there is the point("left" point) on the ascending branch of parabolic trajectory at the height h= 10 m.

The magnitude of the vertical component of velocity v(y) at the “left” point is equal to the magnitude v(y) at the “right” point (their directions are opposite). Vertical component of the initial velocity and vertical component of velocity at height 10 m are related as

v(oy)² - v(y)² = 2•g•h, =>

v(oy) =sqrt {2•g•h+v(y)²} =

= sqrt {2•g•h+(v•sin30)²} =

= sqrt {2•9.8•10+(20•sin30)²} =17.2 m/s.

v(o) =sqrt{v(ox)²+v(oy)²} =

= sqrt{17.32²+ 17.2²} = 24.4 m/s

tan α =v(oy)/v(ox) = 17.2/17.32=0.99

α =44.8º

**Related Questions**

Physics - A ball player hits a home run, and the baseball just clears a wall 20...

Physics - A ball player hits a home run, and the baseball just clears a wall 17...

Physics - A ball player hits a home run, and the baseball just clears a wall 17....

physics - A ball player hits a home run, and the baseball just clears a wall 17....

Math - A baseball player hits a pitch when the ball is 2 feet off the ground. ...

math - a baseball player hits sa pitch when the ball is 2 feet off the ground. ...

Physics - A baseball player hits a home run that just barely clears the 12m high...

Physics - A baseball player hits a home run that just barely clears the 12m high...

Physics - a baseball player leads off the game and hits the long home run. The ...

physics - Is it true that when a baseball player hits a home run, the baseball ...