Projectile motion stunt doubles

[pinkfloyd12]

In the movie Thelma and Louise, the two actresses drove off a cliff at the end. In preparation for the scene, their stunt doubles determined that the cliff was 50.0 m high. The director wants the car to land 90.0 m from the base of the cliff close to the camera location. How fast must the car be traveling in order to land at this location? [101 km/h]

I found this question on the internet, I had been doing projectile questions all night with great success, however for some reason i can't seem to get 101km/hr for this question. It doesn't make sense.

If it is driven off the cliff, then inital vertical velocity is 0, therefore gravity will pull it down in 5.1 seconds no? So in that 5.1 seconds the car must have enough vertical velocity to go 90m, traveling at 17.6m/s for 5.1seconds will take you 90m.

Whats the deal? Is that answer wrong?

 

[RoryP]

just to clear things up how did you calculate 5.1 seconds?

 

[rock.freak667]

If it is driven off the cliff, then inital vertical velocity is 0, therefore gravity will pull it down in 5.1 seconds no?

What did you use to obtain this time?

 

[RoryP]

i can obtain the correct answer, we just need to see where you got 5.1 seconds from?

 

[tiny-tim]

Welcome to PF!

Hi pinkfloyd12! Welcome to PF!

… the cliff was 50.0 m high.
…
If it is driven off the cliff, then inital vertical velocity is 0, therefore gravity will pull it down in 5.1 seconds no?

Noooo

 

[pinkfloyd12]

Whoooops. Got it. Units to the maximum.