Absolutely not but how does momentum transfer to surrounding (ground, air particles)?
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3 Answers
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It is awe inspiring to realize that when the bus stops most of the momentum is taken up by the earth.
As dmckee comments, there are two conservation laws involved in braking. The energy of the bus has to go somewhere, and the momentum too, as they are independently conserved.
Part of the energy goes to heat, in the brakes and on the contact ground/wheels. Heat means photons, so photons may take away some momentum. But most momentum through friction is transferred to the ground . The earth moved after all :).
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$\begingroup$ Introducing the energy loss mechanisms might not be useful for students at the level of this question unless you clearly distinguish the two questions (where doe the momentum go from where does the energy go). $\endgroup$ Commented Dec 18, 2015 at 16:14
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'Suddenly' doesn't mean that a moving bus can stop within no-time(Instantly).
Bus stops in short duration,and the friction between tyre and the ground will take away the momentum (while ignoring any other friction).
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A bus driving along the surface of the earth has angular momentum relative to the center of the earth. For mass $m$ and velocity $v$ it is $mvR$ where $R$ is the radius of the earth.
When it brakes, there will be a for $F$ for duration $\Delta t$ giving a change in momentum of the bus of $f\Delta t$, change in angular momentum of $F\delta t R$. That is the same angular momentum given to the earth (equal and opposite force - just as the earth applies a force to the bus, so the bus applies a force to the earth).
If a 10,000 kg bus is driving at 72 km/hr (20 m/s) along the equator, and it brakes, the change in rotation speed of the earth can be calculated as $\frac{\Delta L}{I}=10,000\cdot 20\cdot 6.3\cdot 10^6 / 8\cdot 10^{37=}1.6\cdot 10^{-36} s^{-1}$ which means a change in the length of the day of $1.4\cdot 10^{-24}$ s.
It's a big, big rock!
As for the energy: the kinetic energy change for the earth is negligible compared to the generation of heat in the brakes and tires of the bus.
