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The W and Z bosons carry the weak force

In brief

The photon carries the electromagnetic force. The gluon carries the strong force. One force from the exchange pattern is still missing its carrier: the weak force.

The exchange sentence repeats one more time, with a twist. The weak force fits the same sentence, but it has two exchange particles, not one.

The weak force's two exchange particles are called the W boson and the Z boson. Matter particles interact by exchanging W and Z bosons — the W and Z bosons carry the weak nuclear force.
matter particlematter particleW or Z boson
Matter particles interact by exchanging W and Z bosons.

The weak force acts on all matter particles, quarks and leptons alike. So W and Z bosons can pass between any of them.

You saw that the weak force can change one type of particle into another. When a neutron changes into a proton, a W boson carries that interaction.

Careful with the letter W. In this topic it names a particle, the W boson. It does not mean work, and it does not mean the watt.

A neutron changes into a proton. Which boson carries this interaction?

Only the weak force changes one type of particle into another.

A particle-changing weak interaction is carried by the W boson.

A W boson carries the interaction.

Check what you know

Which two bosons carry the weak nuclear force?

Which particles can interact by exchanging W and Z bosons?

Which force does the Z boson carry?

The weak force changes one type of particle into another. Which boson carries that interaction?

Which statement about the Z boson is correct?

A neutrino and a quark exert a force on each other by exchanging a Z boson. Which force is this?