[gerardseal (OP)]

I have been trying for a very long time to task this problem, but it does not work for me.
Can anyone help me?
You are on the roof of the physics building, 46.0 m above the ground. Your physics professor, who is 1.80 tall, is walking along side the building at a constant speed of 1.20 m/s. If you wish to drop an egg on your professor's head, how far from the building should the professor be when you release the egg? Assume that the egg is in free fall.Take the free fall acceleration to be 9.80 m/s2.
Thank you all very much for your answers! I also found on <link removed> a detailed description of the solution to this problem. I needed accurate calculations.

[Halc]

I have been trying for a very long time to task this problem, but it does not work for me.
Can anyone help me?

It is traditional on homework problems for the OP to show some effort, so that help can show the point at which the understanding is incorrect.
Nevertheless, the problem as worded is trivial.

You are on the roof of the physics building . . . Your physics professor . . . is walking along side the building at a constant speed . . . If you wish to drop an egg on your professor's head, how far from the building should the professor be when you release the egg?

That's easy, without any additional information, he needs to be the distance from the edge from which the egg is dropped, which is about an arms length if you hold the egg out. Since he's walking along side the building, his distance from it never changes.
As for the acceleration, friction, height of building or professor, none of these factors matter. They only affect when you should release the egg, not the distance from the building the prof maintains as he walks along side it.

[alancalverd]

And the drop time depends on the freshness and species of the egg. With a 44.2 m drop a stale hummingbird egg will reach a constant terminal speed but a fresh ostrich egg will probably still be accelerating when it hits him.

[Bored chemist]

And the drop time depends on the freshness and species of the egg. With a 44.2 m drop a stale hummingbird egg will reach a constant terminal speed but a fresh ostrich egg will probably still be accelerating when it hits him.

Or you can read the question.

Assume that the egg is in free fall.

.

But the bit of the question you really need to read is this.

walking along side the building

As Halc pointed out.

[Petrochemicals]

What is the wind resistance upon the egg? This is usually neglected but should not be. If you just throw the egg hard you probably stand a better chance, aim head on as he is walking toward your position as a face shot is always better. Aiming head on will also stop any errors in timing, he will be in the position for far longer

[Bored chemist]

What is the wind resistance upon the egg?

The wind resistance on the egg is a thing you have been told to ignore.

Assume that the egg is in free fall

[alancalverd]

Or you can read the question.
Quote from: gerardseal on Today at 15:14:57
Assume that the egg is in free fall.
.

If that were the case then you and the professor would suffocate.

[alancalverd]

But the bit of the question you really need to read is this.


Quote from: gerardseal on Today at 15:14:57
walking along side the building
As Halc pointed out.

and answered it before I had read the question.

[Bored chemist]

Or you can read the question.
Quote from: gerardseal on Today at 15:14:57
Assume that the egg is in free fall.
.

If that were the case then you and the professor would suffocate.

I'm sure that both of us have sat in an exam or schoolroom and made calculations assuming free fall conditions (Knowing that if we tried to "show off" and include it, we would get the wrong answer) without asphyxia.

Why would it be different now?

[hamdani yusuf]

walking along side the building

The answer could be quantized if this statement is replaced with walking toward the building (assuming there's an open door to go through).

[gerardseal (OP)]

Thanks! But I'm not sure if I can write an answer in this form. Can you do this more mathematically?

[vhfpmr]

Thanks! But I'm not sure if I can write an answer in this form. Can you do this more mathematically?

You are given some information that enables you to find the distance that the egg falls, and some information that connects the distance the professor walks with the time that the egg takes to fall. What can you do with all that? Have you learnt any equations with these variables in?

[Origin]

The answer could be quantized if this statement is replaced with walking toward the building (assuming there's an open door to go through).

Huh?

[Bored chemist]

The answer could be quantized if this statement is replaced with walking toward the building (assuming there's an open door to go through).

Huh?

I don't think "quantized" is the right word.
But it could be made into a more sensible maths problem by making that assumption.

[alancalverd]

I'm sure that both of us have sat in an exam or schoolroom and made calculations assuming free fall conditions (Knowing that if we tried to "show off" and include it, we would get the wrong answer) without asphyxia.

Why would it be different now?

Because Torricelli performed his experiments before I was born, and airplanes fly. Youngsters may have seen experiments in free fall where the ambient air was also in free fall, in planes and spacecraft, and some pensioners will recall seeing a hammer and feather in free fall towards the moon. Admittedly those who took their exams after Aristotle and before Torricelli  would have a different idea of free fall, but those whose education predated Galileo would have  wanted to know the mass of the egg.

[alancalverd]

Thanks! But I'm not sure if I can write an answer in this form. Can you do this more mathematically?

The equations of linear motion are

v = u + at
s = ut + ½at²
v² = u² + 2as

where v = final velocity
u = initial velocity
a = acceleration
s = distance
t = time

So you can apply them to the egg and the professor. (Hint: you only need one of the equations)

But Halc's reply remains the truth.

[Petrochemicals]

I'm sure that both of us have sat in an exam or schoolroom and made calculations assuming free fall conditions (Knowing that if we tried to "show off" and include it, we would get the wrong answer) without asphyxia.

Why would it be different now?

. Youngsters may have seen experiments in free fall where the ambient air was also in free fall, in planes and spacecraft, and some pensioners will recall seeing a hammer and feather in free fall towards the moon.

I imagine if you dropped a feather at the edge of a tall build g it would immediatley rise due to the upward air effects.

[alancalverd]

Thus saving all the pointless effort that birds put into flying. But how do they come down to feed?

[Bored chemist]

Thus saving all the pointless effort that birds put into flying. But how do they come down to feed?

Powerdive.

[Bored chemist]

I'm sure that both of us have sat in an exam or schoolroom and made calculations assuming free fall conditions (Knowing that if we tried to "show off" and include it, we would get the wrong answer) without asphyxia.

Why would it be different now?

Because Torricelli performed his experiments before I was born, and airplanes fly. Youngsters may have seen experiments in free fall where the ambient air was also in free fall, in planes and spacecraft, and some pensioners will recall seeing a hammer and feather in free fall towards the moon. Admittedly those who took their exams after Aristotle and before Torricelli  would have a different idea of free fall, but those whose education predated Galileo would have  wanted to know the mass of the egg.

My mum was a teacher and, when she retired she took to marking exams. That's not a very unusual story.
She talked about one of the more challenging aspects of the process- the issue of a candidate who failed to read the question but, while giving an answer to the wrong question, demonstrated that they had a good understanding of the topic that was being tested.

If my memory serves me, it's called "departure from rubric",
I wonder how often you called it into play (presumably unknowingly).