A 63.0-kg sprinter starts a race with an acceleration of 4.20 m/s2 . what is the net external force on him?

1 answer:

8 0

From Newton's second law of motion, it was stated that the net external force on a certain object can be calculated by multiplying its mass to the acceleration. This can mathematically be expressed as,
Fnet = m x a
where m is mass and a is acceleration.

Substitute the known values to the equation,
Fnet = (63 kg) x (4.20 m/s²)
Fnet = 264.6 kg m/s²

ANSWER: <em>Fnet = 264.6 N</em>

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Answer:

less than stating velocity due to friction and air resistance.

Explanation:

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3 years ago

The ground state energy of an oscillating electron is 1.23 eV. How much energy must be added to the electron to move it to the t

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Answer:

The energy that must be added to the electron to move it to the third excited state is -1.153 eV

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Explanation:

Given;

Energy of electron in ground state (n = 1 ) = 1.23 eV

E₁ = 1.23 eV

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where;

E₁ is the energy of the electron in ground state

n is the energy level,

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The energy that must be added to the electron to move it to the third excited state is -1.153 eV

For fourth excited state, n = 5

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3 years ago

The speed at which an object falls and the acceleration at which it falls are

allochka39001 [22]

No, the speed at which an object falls is not equal to the acceleration at which it falls.

Answer:

Option B

Explanation:

Speed is defined as how fast an object can cover a specific distance and in what time it covers. So it is measured as the ratio of distance covered to the time taken to cover that distance. While acceleration is the rate of change of velocity. Moreover, speed is a scalar quantity and acceleration is a vector quantity. So most of the times, the direction will play an important role in the varying values of speed and acceleration. Also, acceleration of an object will depend upon the force and mass of the object. Thus, speed and acceleration will not attain same value always.