A woman throws a ball at a vertical wall d = 5.0 m away.

AI Thread Summary
The discussion revolves around a physics problem where a woman throws a ball at a vertical wall 3.2 m away, with an initial velocity of 14 m/s at a 45° angle. Key calculations include the time the ball is in the air before hitting the wall, which is found to be 0.323 seconds, and the height at which it strikes the wall, calculated to be 4.29 m above the ground. After the ball hits the wall, its horizontal velocity reverses while the vertical component remains unchanged, requiring a new analysis for its trajectory post-impact. Participants suggest calculating the horizontal and vertical components of the ball's velocity upon impact to solve for its subsequent motion. The discussion emphasizes the importance of understanding projectile motion and the effects of a bounce in this scenario.
cbking1306
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A woman throws a ball at a vertical wall d = 3.2 m away. The ball is h = 1.6 m above ground when it leaves the woman's hand with an initial velocity of 14 m/s at 45°. When the ball hits the wall, the horizontal component of its velocity is reversed; the vertical component remains unchanged. (Ignore any effects due to air resistance.)

(a) Where does the ball hit the ground?
m (away from the wall)

(b) How long was the ball in the air before it hit the wall?
s

(c) Where did the ball hit the wall?
m (above the ground)

(d) How long was the ball in the air after it left the wall?
s

I found part B was .323s and part C is 4.29m. I don't know how to solve the second part.
 
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cbking1306 said:
A woman throws a ball at a vertical wall d = 3.2 m away. The ball is h = 1.6 m above ground when it leaves the woman's hand with an initial velocity of 14 m/s at 45°. When the ball hits the wall, the horizontal component of its velocity is reversed; the vertical component remains unchanged. (Ignore any effects due to air resistance.)

(a) Where does the ball hit the ground?
m (away from the wall)

(b) How long was the ball in the air before it hit the wall?
s

(c) Where did the ball hit the wall?
m (above the ground)

(d) How long was the ball in the air after it left the wall?
s

I found part B was .323s and part C is 4.29m. I don't know how to solve the second part.

You should have calculated the horizontal and vertical components of the ball's velocity when it struck the wall. Use the hint at the end of the problem statement and figure out the trajectory of the ball after it bounces off the wall. (bold portion).
 
After the ball hits the wall, you have to start a new problem with an initial velocity and height again (except going in the opposite direction).

Chet
 
I found the initial velocity in the x direction to be 14cos(225)=5.14 m/s and the initial velocity in the y direction to be 14sin(225)=-13.02 m/s. The equation I am trying to plug it into is V1y(SQ)=V0y(SQ)+2aΔt
 
sorry meant Δy at the end of that equation
 
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