- #1

WeldingStuff

- 6

- 0

## Homework Statement

A ball is thrown upwards at 20 m/s at an angle of 15 degrees to ground.

How long until the ball touches the ground?

Givens for vertical:

Acceleration = -9.8m/s2

v1= 5.2 m/s (20SIN15)

v2=0

displacement=0

t=?

Givens for horizontal

Acceleration= 19.3 m/s (20COS15)

Displacement= ? (perhaps work back from displacement on horizontal to get the time?)

t=?

## Homework Equations

DeltaD= (V1)(DeltaT) + (.5)(A)(DeltaT)

Answer should be 0 OR 1.1s for T ( I don't understand how you are to get two answers)

## The Attempt at a Solution

0=(5.2)(detlaT) +(0.5)(-9.8)(deltaT)[/B]

?? ?? ??

The textbook suggests to use this equation and not the other 4.

Also I am not sure if displacement is zero for the horzontal given that V=D/TStumped for hours.

Nobody I can ask for help