How does a massless photon impart force?

[dev_c0t0d0s0]

I've been watching a lot of physics videos lately and a couple of said that photons are massless. What I don't understand is how a massless photon can impart force? Like the ideas of having a laser propel a deep space probe.

 

[berkeman]

Welcome to the PF.

Have you read through these links already?

https://en.wikipedia.org/wiki/Photon#Physical_properties
https://www.khanacademy.org/science/physics/quantum-physics/photons/v/photon-momentum

 

[sophiecentaur]

how a massless photon can impart force

A Massless object can still have Momentum. It is the Momentum of a Photon that imparts a change of Momentum (i.e. a force) on an object that it hits.