1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Natalka [10]
2 years ago
9

Sprinters push off from the ball of their foot, then bend their knee to bring their foot up close to the body as they swing thei

r leg forward for the next stride. Why is this an effective strategy for running fast?
Physics
1 answer:
Nataliya [291]2 years ago
7 0

There are two interchangeable concepts that can be applied to this theory. The first one is the moment of Inertia and the second the perioricity. When the runners put their leg forward they reduce their moment of inertia allowing their center of mass to maintain the speed they carry and not waste energy. In this way when they swing, the leg begins to act as a kind of pendulum, and remember that the pendulum is directly proportional to the length, that is,

T = 2 \pi \sqrt {l / g}

In this way, by bringing their legs closer they reduce the distance and make the period shorter.

You might be interested in
Which items in this image are electrically conductive? Check all that apply.
balu736 [363]

Answer: a and d

Explanation: A.) the power lines themselves

B.) the wooden pole that supports the lines

C.) the rubber soles on the worker’s boots

D.) the metal tools the worker uses

E.) the wooden ladder leaning against the lines

4 0
3 years ago
I need your opinion on this
DiKsa [7]
Block that fool, move on, take a nice warm bath, but on some music and vibe dawg, it might be hard to get over something like this, but just know that person was in the wrong the whole time.
5 0
2 years ago
Two children of about the same weight are playing at the playground. They both climb up to the top of a small tower. One slides
olya-2409 [2.1K]

Answer:

D

Explanation:

D) The overall work done by gravity is zero  

This statement is correct .

If m be the mass of each of the children and h be the height of tower

work done by gravity on the boys in going up = - mgh

it is so because force applied by gravity = mg downwards and displacement

is upwards

work done will be negative = - mgh

Work done by gravity on boys when they come down = + mgh because both force and displacement are downwards .

Hence total work done = - mgh + mgh = 0.

The children will have same kinetic energy as the inclined surface is friction-less so no energy will be dissipated hence addition of energy to boys in both the cases will be same.

4 0
3 years ago
Is there a definite end to our atmosphere?
Irina18 [472]
There is no definite end to earths atmosphere, but technically the border between the outer space and earth gets thinner as you move up from the earths surface. The Karman line is the closest definition there is which describes the end of the earth's atmosphere, it is 100 km above earth's sea level at approximately 1.56 % of total earth's radius. This describes the boundary between the outer space and the atmosphere.
7 0
3 years ago
Since the Wagon is being pulled down hill is it increasing (C)
Ket [755]
<em>Since the wagon is being pulled down hill with a constant velocity, all the forces of the wagon would be (C) increasing.</em>
<em>You are correct! **</em>
4 0
3 years ago
Other questions:
  • The magnetic field over a certain range is given by B~ = Bx ˆı + By ˆ, where Bx = 2 T and By = 4 T. An electron moves into the
    10·1 answer
  • Astrology is the study of the Earth, Moon, and Stars in space. true or false
    11·2 answers
  • Explain how depression arises from a combination of both genetic and environmental factors
    5·2 answers
  • A mass of 100 g stretches a spring 5 cm. If the mass is set in motion from its equilibrium position with a downward velocity of
    11·1 answer
  • What is the wavelength of a 22.75×109Hz radar signal in free space? The speed of light is 2.9979×108m/s. Express your answer to
    6·2 answers
  • Define Momentum? ......
    13·2 answers
  • Compare the Summer Solstice with the Autumn Equinox. Justify your response in two or more complete sentences.
    12·2 answers
  • In a Rutherford scattering experiment, each atom in a thin gold foil can be considered a target with a circular cross section. A
    14·1 answer
  • The brakes application to a car produce an acceleration of 6ms2 in the opposite direction to the motion .If the car takes 2 seco
    15·1 answer
  • A bicyclist rides 2.93 km due east, while the resistive force from the air has a magnitude of 8.65 N and points due west. The ri
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!