# The Physics of a Tesla Model X Pulling a Boeing 787

WIRED | 5/17/2018 | Rhett Allain
Level 3
Click For Photo: https://media.wired.com/photos/5afde1974de59042113f0f21/191:100/pass/qantastesla.jpg

This is pretty cool—an electric car pulling a full size commercial aircraft, apparently for the first time ever. In particular, it is a Tesla Model X pulling a Quantas Boeing 787. There are a million reasons this is cool, but I think we should just jump to the coolest ones: the physics questions.

Does the mass of the plane matter?

#### Boeing - Dreamliner - Takeoff - Weight - Kg—but

The Boeing 787-9 Dreamliner has a maximum takeoff weight of 254,000 kg—but this one was empty and had a mass of 130,000 kg. Yes, that's pretty massive—but it doesn't matter. In fact, a human could even pull a full-sized aircraft. Don't believe me? How about this guy:

Mass doesn't matter. If there is only one force on an object, that object will accelerate. Here's an example you can try yourself (maybe). Go down to the dock and place one foot on a large boat and the other foot on the wooden dock. Now push. Guess what? It moves (assuming it's not tied down). That small force from your foot does indeed cause the boat to increase in speed at least for a little bit. Once it starts moving, there is a force from the water that prevents it from speeding up.

#### Forces - Objects - Velocity - Object - Mass

Forces cause objects to change velocity. If the object has a large mass, that just means the change in velocity is smaller—but it's still a change. So the mass of the plane doesn't really matter. If there were no other forces, I could push an aircraft carrier. But there are other forces. There is friction.

Why is there a frictional force on the plane?

#### Forces - Force - Parallel - Ground - Direction

We can think of most frictional forces as a force parallel to the ground and acting in the opposite direction as the motion of the object. There are really two types of friction that come into play when pulling a plane....