Ok so this problem appeared in my online chem homework, but it looks alot more like a physics problem. I have no idea how to do it
A 203 lb man eats an order of French Fries consuming 250 Cal of food energy. Afterwards he feels guilty and decides to work off the excess calories by walking up seven flights of stairs 3.0 times. (The total height of seven flights of steps is 110 ft) Calculate the energy the man has burned off by doing the exercise. Assume that work is done only when walking up the steps. Note: 1 Cal = 4.184 kJ
203lbs= 902.94N
110ft= 33.528m
902.94*33.528*3=90 822J
90822J* 1Calorie/(4184J) = 21.7
I did not check the numbers, but the steps are correct.
STOP CHEATING ON YOUR HOMEWORK
never.
To solve this problem, we need to calculate the energy burned off by the man during his exercise of walking up seven flights of stairs three times.
First, let's convert the weight of the man from pounds to kilograms. We know that 1 pound is approximately equal to 0.4536 kilograms, so the man's weight in kilograms would be:
203 lb * 0.4536 kg/lb = 92.0752 kg
Next, let's calculate the total distance the man has walked. Since the height of seven flights of stairs is given as 110 ft, and the man walks up the stairs three times, the total distance can be calculated by multiplying the height by the number of times he walks up the stairs:
Total distance = 110 ft * 3 = 330 ft
Next, let's convert the distance from feet to meters. We know that 1 ft is approximately equal to 0.3048 meters, so the total distance in meters would be:
330 ft * 0.3048 m/ft = 100.584 m
Now, we can calculate the work done by the man using the formula:
Work = Force * Distance
Assuming the man's body weight acts as the force, we can calculate the force using the formula:
Force = Weight * Gravity
Where gravity is approximately equal to 9.8 m/s^2.
Force = (92.0752 kg * 9.8 m/s^2) = 902.862 kg*m/s^2 or N
Now, let's calculate the work done:
Work = Force * Distance = 902.862 kg*m/s^2 * 100.584 m = 90746.075088 J
Finally, let's convert the work done from joules to kilojoules using the conversion factor:
Work in kJ = 90746.075088 J * (1 kJ / 1000 J) ≈ 90.75 kJ
Since 1 Cal = 4.184 kJ, let's convert the energy burned off from kilojoules to calories:
Energy burned off = 90.75 kJ * (1 Cal / 4.184 kJ) ≈ 21.71 Cal
Therefore, the man has burned off approximately 21.71 calories by walking up seven flights of stairs three times.