# Thread: Downwind faster than the wind

1. Originally Posted by Motor Daddy
I've seen people like you use a wrench as a hammer.
I feel like I'm doing that even as we speak.

2. Originally Posted by KitemanSA
Seems you answered yourself twice. POWER = force*velocity. Simple.
You're in the same boat as A.T.

3. Originally Posted by Aqueous Id
I feel like I'm doing that even as we speak.
I'm not a doctor, but I've read that people that smack themselves on the head with a wrench (like you're doing as we speak) are a few sandwiches short of a picnic. I'm just sayin'.

4. Originally Posted by Motor Daddy
I'm not a doctor, but I've read that people that smack themselves over the head with a wrench (like you're doing as we speak) are a few sandwiches short of a picnic. I'm just sayin'.
I've got a cure for you practicing without a license. You can play car mechanic with the wind car. I have a question for you. If the wind presents a 100 N force on the blades of this thing, how much force is being applied to the mast at that location?

5. Originally Posted by Motor Daddy
How much work was done? What distance was the object lifted? How much time did it take to lift the object that distance?
Please state the whole question. What is given? What is asked?

6. Originally Posted by Aqueous Id
Yes , I was here during the prior confusion over that. Hopefully it's making some sense to you.
So it WAS you here earlier, and then you go away for a short time and come back and claim you just got here?

7. Originally Posted by A.T.
Please state the whole question. What is given? What is asked?
As I stated earlier:

You claim power=force*velocity.

I lifted a 29 lb object at a velocity of 16 ft/s. How much work was done?

8. Originally Posted by Motor Daddy
So it WAS you here earlier, and then you go away for a short time and come back and claim you just got here?
I have not been following the active discussion over the last 5 or 6 hours. I avoided the lengthier higher precision answer since you are squeamish about lots of facts and numbers.

9. Originally Posted by Motor Daddy
I lifted a 29 lb object at a velocity of 16 ft/s. How much work was done?
Not enough information to compute work.

10. Originally Posted by A.T.
Not enough information to compute work.
That's correct MD, for all we know you are still doing the work, the way you stated it.

11. Originally Posted by Motor Daddy
As I stated earlier:

You claim power=force*velocity.

I lifted a 29 lb object at a velocity of 16 ft/s. How much work was done?
Your action requires a power of .84 horsepower. (Note work does not equal power.)

12. Originally Posted by Motor Daddy
You're in the same boat as A.T.
Then it is an excellent boat and I'm in good company.

13. Originally Posted by Motor Daddy
As I stated earlier:

You claim power=force*velocity.

I lifted a 29 lb object at a velocity of 16 ft/s. How much work was done?
Can't know without the duration unless you assume an instantaneous velocity and a set g field.

14. Originally Posted by Motor Daddy
As I stated earlier:
You claim power=force*velocity.
I lifted a 29 lb object at a velocity of 16 ft/s. How much work was done?
I will answer your question as soon as you answer my exactly equivalent question:

I eat one banana per day.
How many how many bananas have I eaten?

By stating "I lifted a 29 lb object at a velocity of 16 ft/s", you are giving us power which is a rate which is exactly the same as my saying "I eat one banana per day".
When you ask "How much work was done", you are asking for work which is a quantity which is exactly the same as my asking "How many how many bananas have I eaten".

I'm not sure precisely what's tripping you up on "power=force*velocity", but the general theme running across all your posts seems to involve either equating a rate with a quantity, or difficulty tracking the relationship between them.

Originally Posted by Motor Daddy
Originally Posted by Aqueous Id
Power = energy / time.
Energy = force * distance
Power = (force * distance) / time
Power = force * (distance / time)
Power = force * velocity.
So let's apply your logic to a simple example:
You lift a 100 lb rock 10 feet away from the center of the earth.
Lifting a 100 lb rock by ten feet is a quantity of work. We can do that quantity of work at a rapid rate in 1/100th of a second with a very large horsepower motor moving the rock at high velocity, or we can can do that quantity of work at a very low rate in 1000 seconds with a very small horsepower motor moving the rock at low velocity.

Time and velocity have no connection to the quantity of work, but time and velocity are central to power (which is the ability to preform work at a specified rate).

15. Originally Posted by Alsee
I will answer your question as soon as you answer my exactly equivalent question:

I eat one banana per day.
How many how many bananas have I eaten?
How do you know you eat one banana per day? Is that a theory of yours or did you actually eat one?

Same goes for velocity. How do you know the velocity if I didn't give it to you?

16. Motor Daddy
Banned
Buh-bye troll

17. Motor Daddy has been given a 1-day ban for trolling and obstructing discussion. However, I've stepped outside my jurisdiction - I mistakenly thought this thread was in Physics and Maths, so MD's ban may yet be reversed.

I'll ask for this diversion on the relationship between power and velocity to be moved to Physics and Maths.

Originally Posted by Alsee
Buh-bye troll
This is not appropriate, Alsee. Bans are not a cause for glee or gloating.

Originally Posted by Motor Daddy
How do you know you eat one banana per day? Is that a theory of yours or did you actually eat one?

Same goes for velocity. How do you know the velocity if I didn't give it to you?
Your irrelevant diversion is obstructing the discussion, Motor Daddy.

Do you understand that Alsee's question is unanswerable, and that your Alsee was using to illustrate why your question is similarly unanswerable?
Knowing the rate of bananas eaten per day doesn't tell you the total bananas eaten.
Similarly, knowing power doesn't tell you work.

18. Thank you Pete.

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