If a 46 kg person walks up two floors in the Physics building (about 10 meters up), this person's potential energy has increased by _____ J.a. 1400 J b. 10,000 J. c. 1000 J. d. 100 J

Respuesta :

Answer:

B. 10000 J

Explanation:

The possible answers are not related to the statement at all. The correct statement is:

If a 100 kg person walks up two floors in the Physics building (about 10 meters up), this person's potential energy has increased by:

From definitions of work and gravitational potential, we get the following formula to calculate the change experimented in the person's potential energy after walking up two floors in the Physics building:

[tex]\Delta U_{g} = m\cdot g \cdot \Delta z[/tex] (1)

Where:

[tex]\Delta U_{g}[/tex] - Change in the gravitational potential energy, measured in joules.

[tex]m[/tex] - Mass of the person, measured in kilograms.

[tex]g[/tex] - Gravitational acceleration, measured in meters per square second.

[tex]\Delta z[/tex] - Change in height, measured in meters.

If we know that [tex]m = 46\,kg[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex] and [tex]\Delta z = 10\,m[/tex], then the change in the gravitational potential energy is:

[tex]\Delta U_{g} = (100\,kg)\cdot \left(9.807\,\frac{m}{s^{2}} \right)\cdot (10\,m)[/tex]

[tex]\Delta U_{g} = 9807\,J[/tex]

The choice that best approximates this answer is B.