Projectile Motion (not on Earth)

[randomphysicsguy123]

Homework Statement

A truck is dropped out of a building that is 20 meters high. When the truck started to fall, it went 1 meter after the first second. After a total of 3 seconds, how high is the truck located from the ground? (Hint: This is not on earth)

Relevant Equations

delta y = vt+1/2at^2

I know I need to solve for acceleration as I am not on Earth and I am assuming I should create a distance vs. time graph. But overall I am unsure what to do. Please help been stuck on this for a while.

 

[PeroK]

Homework Statement:: A truck is dropped out of a building that is 20 meters high. When the truck started to fall, it went 1 meter after the first second. After a total of 3 seconds, how high is the truck located from the ground? (Hint: This is not on earth)
Relevant Equations:: delta y = vt+1/2at^2

I know I need to solve for acceleration as I am not on Earth and I am assuming I should create a distance vs. time graph. But overall I am unsure what to do. Please help been stuck on this for a while.

One metre in one second is an average speed of $1m/s$, right?

 

[randomphysicsguy123]

Correct. But could you provide a bit more insight as what I should do I am really lost.

 

[PeroK]

Correct. But could you provide a bit more insight as what I should do I am really lost.

How is average speed related to acceleration?

 

[randomphysicsguy123]

average speed=d/t
a=change in v/ change in time

 

[PeroK]

average speed=d/t
a=change in v/ change in time

Can you use those to find the acceleration on the mystery planet?

 

[randomphysicsguy123]

Yes I could however I keep getting 1m/s^2 but when xf=xi+vit+1/2a*t2 to check if that statement is true I get .92m/s^2

 

[PeroK]

Yes I could however I keep getting 1m/s^2 but when xf=xi+vit+1/2a*t2 to check if that statement is true I get .92m/s^2

If the acceleration is $1m/s^2$, how far does the object fall in the first second?

 

[randomphysicsguy123]

1 meter

 

[PeroK]

1 meter

If that was a guess it was wrong. Why not use $s = ut + \frac 1 2 a t^2$, with $u = 0$ and $t = 1s$?

Why guess when you have SUVAT equations?

 

[randomphysicsguy123]

Didn't think about that. Regardless, I already turned it in and I used the equation xf=xi+vit+1/2a*t^2, which got me 15.86 meters at 3 seconds. Hope it was right. Thank you for your help.

 

[haruspex]

Didn't think about that. Regardless, I already turned it in and I used the equation xf=xi+vit+1/2a*t^2, which got me 15.86 meters at 3 seconds. Hope it was right. Thank you for your help.

xf=xi+vit+1/2a*t^2 tells you that, starting from rest, the distance is proportional to t². So after three times the time, how many times the distance?