a projectile is fired straight upward at 100m/s. how fast is it moving at the instant it reaches the top of its trajectory

Question

mrnood · Answer

when it reaches the top - it has stopped moving up, but hasn't started to move down - what is its speed?

mathmale · Answer

This problem comes from Physics.  You need to find the equation for vertical velocity for use in this case, where the projectile is fired straight upward.
What is the initial velocity?  The final velocity?  The acceleration?

mathmale · Answer

In this case, the acceleration is constant, so that simplifies the equation for velocity.  What is that equation?

mathmale · Answer

OpenStudy says you are now "offline."  Please, next time you decide to log off, would you inform the person or the people helping you?

mrnood · Answer

@mathmale

You don't needs to do any of this stuff.

The projectile is fired 'straight up'

When a body reaches the 'top of its trajectory' is has 0 vertical velocity, regardless of mass, initial velocity, acceleration, distance etc.