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REVIANNA

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## Homework Statement

Two projectiles are launched simultaneously from the same point above the flat terrain. The initial speeds of the projectiles are the same. Each projectile’s velocity makes the same angle with the horizontal. However, projectile A is launched

**a**bove the horizontal and projectile B is

**b**elow the horizontal.

Consider the entire flights of the projectiles. State which of the projectiles has greater:

1

**-time in the air**

It's A

because

x_f = x_i+v sin(theta) t_f-(0.5*g*(t_f^2))

for A : 0=x_i

**+**v sin(theta) t_f-(0.5*g*(t_f^2))

so t_f =sqrt ((2 v sin(theta)

**+**x_y)/g)

for B : 0=x_i

**-**v sin(theta) t_f-(0.5*g*(t_f^2))

so t_f =sqrt ((2 v sin(theta)

**-**x_y)/g)

and to put it more simply the simulation picture shows it.

**2-horizontal range**

since the horizontal velocity vector is constant and equal for both A and B

and time in the air is more for A

A's horizontal range is obviously larger.

**3-Landing speed**

this is what I thought -

B is thrown with a downward vertical velocity so it would get increased as the acceleration due to gravity is also downwards

and A is thrown with a upward vertical velocity so it would get decreased as the acceleration due to gravity is downwards

and the horizontal velocities are equal so the landing speed of B would be greater.

but the answer says

**that the landing speed is same for both A and B.**

why is it this way? what am I missing?

why is it this way? what am I missing?

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