How many slices of pizza must you eat to walk for 1.0 h at a speed of 5.0 km/h? (Assume your mass is 68 kg).
Our book provides:
-One slice of pizza's energy content is 300 cal, or 1260 KJ.
-To walk at 5 km/h= 380 W of a 68 kg individual.
Thanks!!!
To find out how many slices of pizza you must eat to walk for 1.0 hour at a speed of 5.0 km/h, we need to calculate the total energy expenditure during the walk and then divide it by the energy content of each slice of pizza.
First, let's calculate the energy expenditure during the walk. The power output required for walking is given as 380 W for a 68 kg individual. Power can be calculated using the formula: power = force × velocity.
Since velocity is given as 5.0 km/h, we need to convert it to meters per second (m/s). There are 1000 meters in a kilometer and 1 hour is equivalent to 3600 seconds. So, the velocity in m/s is (5.0 km/h) × (1000 m/km) / (3600 s/h) ≈ 1.39 m/s.
Now we can calculate the force: force = power / velocity = 380 W / 1.39 m/s ≈ 273.38 N.
To find the total energy expenditure during the walk, we multiply the force by the distance traveled. Since the time of the walk is given as 1.0 hour and the speed is 5.0 km/h, the distance traveled is 5.0 km.
Converting the distance to meters: 5.0 km × 1000 m/km = 5000 m.
The total energy expenditure during the walk can be calculated as: energy = force × distance = 273.38 N × 5000 m ≈ 1,366,900 J.
Now, let's find out how many slices of pizza you need to eat to obtain this amount of energy.
The energy content of one slice of pizza is given as 1260 kJ = 1260,000 J.
To find the number of slices, we divide the total energy expenditure during the walk by the energy content of one slice: number of slices = energy / energy content of one slice = 1,366,900 J / 1260,000 J ≈ 1.08.
Therefore, you would need to eat approximately 1.08 slices of pizza to provide the energy required for walking for 1.0 hour at a speed of 5.0 km/h.