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bluebkracer15
Dec 14, 2004, 05:35 PM
Hello can any one help me with this question??
1 An athlete throws the shotput with an initial velocity of 14 m/s at a 40 degree angle from the horizontal. The shotput leaves his hand at a height of 2.2 m above the ground.
a. Determine the x and y components of the initial velocity.

b. Determine how long the shotput is in the air.

c. Calculate the distance the shotput traveled.

Please help me
Thanks

drwls
Jan 8, 2005, 12:22 AM
<<1 An athlete throws the shotput with an initial velocity of 14 m/s at a 40 degree angle from the horizontal. The shotput leaves his hand at a height of 2.2 m above the ground.
a. Determine the x and y components of the initial velocity.>>
The horizontal component is 14 cos 40 = 10.725 m/s and the vertical component is 14 sin 40 = 8.999 m/s.

<<b. Determine how long the shotput is in the air.>>
That is determined by the vertical component. The time t1 going up is such that g t = Vyo = 8.999 m/s. That means t1 = 0.92 s. In that time, the height increases to 2.2 m + (Vyo/2) t1 = 6.34 m. It spends a longer time t2 coming down because it was launched above the ground. (1/2) g (t2)^2 = 6.34 m. t2 = sqrt [2 * 6.34/g] = 1.14 s. Total time in air = t1 + t2 = 2.06s

<<c. Calculate the distance the shotput traveled.>>
Multiply the time in the air by the horizontal velocity component, which does not change. I get 22.09 m.