Two protons (each with rest mass m=1.67×10−27kg) are initially moving with equal speeds in opposite directions. The protons continue to exist after a collision that produces an η0 particle. The rest mass of the η0 is mη=9.75×10−28kg.

Part A

If the two protons and the η0 are all at rest after the collision, find the initial speed v of the protons.

Express your answer as a fraction of the speed of light to three significant figures.

v =c

Part B

What is the kinetic energy Ek of each proton?

Express your answer in millions of electron volts to three significant figures.

Ek =MeV

Part C

What is the rest energy Er of the η0?

Express your answer in millions of electron volts to three significant figures.

Er =MeV

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