How Do You Calculate Average Vertical Velocity in Physics Problems?

AI Thread Summary
To calculate the average vertical velocity of a firefighter climbing a ladder, the height of the wall (9.10m) is used as the vertical distance (d) in the formula Δd/t. The time taken to reach the roof is 15.0 seconds, leading to an average vertical velocity calculation of 9.10m divided by 15.0s. Clarification on whether to use the height of the wall or the ladder length for distance was discussed, with consensus leaning towards the wall height. The conclusion reached is that using the wall height for the calculation makes sense in the context of average vertical velocity. This approach effectively resolves the initial confusion regarding the distance variable.
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Thanks in advance for reading this thread. Here goes the question;

Q: A firefighter climbs up a 10.0m ladder leaning against a vertical wall.
The ladder makes an angle of 25.0 degrees with the wall. The firefighter reaches
the roof in 15.0s

a) What is the height of the wall? 9.10m
b) How far is the base of the ladder from the wall? 4.23m
c) What is the firefighter's average vertical velocity?

I have completed a) & b) as those were straight-forward questions by using Trig.
However, I got stuck on c). I understand that the average vertical velocity is
\Deltad/t, t would be 15.0s but I'm not sure what the value of the d would be.

Could anybody please direct me or give me some advice?

Thank you
 
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Thats a good question. I think you're probably confused as to whether the distance is the length of the ladder or the height of the wall. Personally I'd say height of the wall but this is a subjective issue of semantics. If you have time I'd clarify it with whoever set you the question.
 
If it says average vertical velocity then surely it has to be the height of the wall.
 
Thanks guys, I really appreciate it.
This is a course that I'm taking from adult learning centre.
It's an independent learning so I have to get this done on my own :(

but after getting help from you guys, it really helps me to re-direct from wrong to right.

ANYWAYS! after squeezing out my brain I just put a conclusion.
Because its asking for "vertical" meaning the "wall" in this case,
I've had the height of the wall as D and divide it by 15 seconds to get the answer.
I think that makes sense

Many thanks guys :)
 
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