Answer:D
Explanation:
When the character falls off from cliff he moves away from the observer as he falls down and hence the frequency heard by observer lowers as he falls.
Therefore the pitch of the sound is lower than the original sound and decreasing as he falls
Option D is the correct choice
From the question, The kinetic energy of the fired arrow is equal to the work done by the bale of hale in stopping the arrow.
We make use of the following formula
mv²/2 = F'd................... Equation 1
Where
- m = mass of the arrow
- v = velocity of the arrow
- F' = average stopping force acting on the arrow
- d = distance of penetration
Make F' the subject of the equation
F' = mv²/2d.................. Equation 2
From the question,
Given:
- m = 20 g = 0.02 kg
- v = 60 m/s
- d = 40 cm = 0.4 m
Substitute these values into equation 2
Hence, The average stopping force acting on the arrow is 90 N
Learn more about average stooping force here: brainly.com/question/13370981
Hi there!
We can use the following (derived) equation to solve for the final velocity given height:
vf = √2gh
We can rearrange to solve for height:
vf² = 2gh
vf²/2g = h
Plug in the given values (g = 9.81 m/s²)
(13)²/2(9.81) = 8.614 m
We can calculate time using the equation:
vf = vi + at, where:
vi = initial velocity (since dropped from rest, = 0 m/s)
a = acceleration (in this instance, due to gravity)
Plug in values:
13 = at
13/a = t
13/9.81 = 1.325 sec
<span>What I have here is exactly the same problem, however, with the time changed to 19 mins:
metabolic energy = metabolic power*time = 1.150*19*60 = 1.311 kJ..corresponding to 1.311/4.186 = 313,2 Cal or kcal
If we reasonably assume a metabolic eff.cy of 20%, it means we need to assume food for 1500 Cal approx.
Just plug the value t=15min to the equation and you will surely get the correct answer.
I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!
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