Question

In order to increase the amount of exercise in her daily routine, Tara decides to walk up the five flights of stairs to her car instead of taking the elevator. Each of the steps she takes are 18.0 cm high, and there are 12 steps per flight.

(a)

If Tara has a mass of 55.0 kg, what is the change in the gravitational potential energy of the Tara-Earth system (in J) when she reaches her car?

J

(b)

If the human body burns 1.5 Calories (6.28 ✕ 10³ J) for each ten steps climbed, how much energy (in J) has Tara burned during her climb?

J

(c)

How does the energy she burned compare to the change in the gravitational potential energy of the system?

Eburned

ΔU

=

Answer 1

(a) C APE = mgsh & (55kg ) (9.8 m/8²) (5x 12 x 0.18m) APE - 5821.25 Aboud to 1285 stell x 6:28 210°5 = 37680.J ratio : to 12x5 Steps 6 10 stepe X 6.28 x 10 - J byoned 37680 o = 6.47 ratio & 5821.2