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tresset_1 [31]
1 year ago
13

A 55 kg track and field athlete has an average power output of 5.4 kW during the 200 meter dash. How quickly did she finish the

race?
Group of answer choices

a. 20 s

b. 22 s

c. 23 s

d. 18 s
Physics
1 answer:
olga_2 [115]1 year ago
5 0

The time taken for the athlete to finish the race is 20 s (Option A)

<h3>What is power? </h3>

Power is simply defined as the rate at which work is done. It can be expressed mathematically as

Power (P) = work (W) / time (t)

But

Work = weight × distance

Therefore,

Power = (weight × distance ) / time

<h3>How to determine the time </h3>
  • Mass (m) = 55 Kg
  • Acceleration due to gravity (g) = 9.8 m/s²
  • Weight = mg = 55 × 9.8 = 539 N
  • Power (P) = 5.4 KW = 5.4 × 1000 = 5400 W
  • Distance (d) = 200 m
  • Time (t) =?

Power = (weight × distance ) / time

5400 = (539 × 200) / t

5400 = 107800 / t

Cross multiply

5400 × t = 107800

Divide both side by 5400

t = 107800 / 5400

t = 20 s

Learn more about power:

brainly.com/question/5684937

#SPJ1

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Answer:

c large, spherical body that orbits in a clear path around a star

Explanation:

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7 0
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A 50.0 kg child stands at the rim of a merry-go-round of radius 1.50 m, rotating with an angular speed of 3.00 rad/s. (a) what i
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Weight of the child m = 50 kg 
Radius of the merry -go-around r = 1.50 m
 Angular speed w = 3.00 rad/s
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1.5
 Centripetal Acceleration a = 13.5m/sec^2
 (b)The minimum force between her feet and the floor in circular path
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/ 1.5
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8 0
3 years ago
A notebook sitting on a desk has 19 j of potential energy. What is the total mechanical energy of the notebook?
Alex17521 [72]

The total mechanical energy of the notebook is <u><em>19J</em></u>.

Mechanical energy is the sum of potential energy and kinetic energy.  It has no kinetic energy, because it's not moving.  So its potential energy is all the  mechanical energy it has.

3 0
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Read 2 more answers
A. Calculate the approximate number of atoms in a bacterium. Assume that the average mass of an atom in the bacterium is ten tim
ludmilkaskok [199]

Answer:

a. Approximate umber of atoms = 10¹¹

b. number of atoms = 50 atoms thick

Note: The question is missing some parts. The complete question is as follows; Calculate the approximate number of atoms in a bacterium. Assume that the average mass of an atom in the bacterium is ten times the mass of a hydrogen atom. (Hint: The mass of a hydrogen atom is on the order of 1×10⁻²⁷ kg and the mass of a bacterium is on the order of 1×10⁻¹⁵ kg)

Explanation:

a. Approximate umber of atoms = mass of bacterium / 10 * mass of hydrogen

number of atoms = 10⁻⁵/ 10 × 10⁻²⁷

number of atoms = 10¹¹ atoms

b. The cell membrane is 10-8 m thick while the hydrogen atom has a diameter of 10-10  m.

The number of atoms in the cell membrane = d1 / 2 × d2

where d1 = diameter of cell membrane; d2 = diameter of hydrogen atom

The number of atoms in the cell membrane = 10⁻ / 2 × 10⁻¹⁰ = 50 atoms

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harina [27]

Answer:

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Explanation:

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