What is a pantograph and why does the MBTA Green Line use them?

A pantograph is the flexible, angled arm on the top of the trolley that connects the train to overhead power lines.

Trolley Slide - Boston T MBTA #3522 LRV Transit Train 1981 Special Pantograph

Pantograph problem halts service on part of MBTA Green Line

Disabled Green Line train brings in more MBTA shuttle buses – NBC Boston

Lego model I designed of the Green Line trains! : r/boston

Railway Age/RT&S LRT Conference Spotlights the Tech Side - Railway Age

MBTA GREEN LINE: C-Cleveland Circle via Beacon St.

Boston: Subways, Wonderland, Trams and Mattapan

Video shows Green Line passengers evacuating after power problem

MBTA Green Line

Riders forced to walk on tracks, take shuttles after electrical problems shut down service on part of Green Line - Boston News, Weather, Sports

Lego model I designed of the Green Line trains! : r/boston

How A Streetcar Works - Boston Streetcars

TIL the MBTA has an underground Emergency Training Center complete with Silver Line, Green Line, and Blue Line train car replicas. It includes an integrated sound system to emulate crowds, gunshots and

MBTA AnsaldoBreda Type 8 - Wikipedia