# Will Running Increase Spit-Distance? Experimenting with Physics!

• Barfolumu
In summary, the conversation discusses whether running before spitting would increase the distance the spit travels. The conclusion is that it would increase the distance, as the spit already has the speed of the runner and the additional force from spitting adds to it. This can be compared to pushing a barrel off a tall building or a moving airplane. Whether the runner stops or continues running, the distance will increase.

#### Barfolumu

Inspired by http://www.news.com.au/story/0,23599,23696646-13762,00.html" [Broken].

Would running before you spit increase the distance your spit travels? I figure, most of the energy comes from your mouth, and you'd probably stop at the end of your run, so would a "running start" increase the distance?

Last edited by a moderator:
I would say that it increases the distance, assuming that you spit first and then stop running. The reason is that the spit inside you already has the speed of your moving and when you spit you add to that speed. So by the time the spit hits the ground (which is independent of horizontal velocity, so same in both running and non running cases), it has traveled further.

Think of it as pushing a barrel of a tall building vs pushing a barrel of a moving air-plane. Both of them seem to me be very common elementary physics problems, so I'm guessing you have come across them before. :)

Yes, it would increase the distance. This would be true whether you stop when you spit, or keep going. But of course, if you keep going, it will only increase the distance as measured by a stationary observer, your spit will not travel farther from you (indeed, it will not travel as far from yourself, as you would create a slight headwind by running.

## 1. How does running affect spit-distance?

Running increases spit-distance due to the increased force and momentum generated by the body during the activity. This results in a longer distance that the spit can travel.

## 2. Is there a specific speed at which running will increase spit-distance?

The speed at which running will increase spit-distance can vary depending on the individual's strength and technique. However, generally, the faster the running speed, the greater the increase in spit-distance.

## 3. Will running on different terrains affect spit-distance?

Yes, running on different terrains can affect spit-distance. For example, running on a flat and smooth surface will likely result in a longer spit-distance compared to running on a rough or uneven surface.

## 4. Are there any other factors besides running speed that can affect spit-distance?

Yes, there are other factors that can affect spit-distance, such as the angle and force at which the spit is released, the moisture content of the spit, and environmental factors like wind speed and direction.

## 5. Can running uphill or downhill affect spit-distance?

Yes, running uphill or downhill can affect spit-distance. Running uphill requires more force and energy, resulting in a longer spit-distance, while running downhill may decrease spit-distance due to the decrease in force and momentum.