The lateral displacement distance through which the tongue rail travels at the switch toe to allow train movement is termed_________________?
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Answer: C. throw of the switch
Explanation
The throw of the switch refers to the lateral distance that the tongue rail moves at the switch toe to shift the train route. This precise lateral displacement creates enough space for wheel flanges to pass safely without mechanical interference. Operating point machines stroke the tongue rail across this exact measured distance during route setting operations. Turnouts utilize movable tongue rails tapering to a fine point at the switch toe to direct train wheels onto diverging tracks. Stock rails remain fixed while adjacent tongue rails shift laterally to establish the desired running path. Signaling and interlocking mechanisms control this switch movement to prevent conflicting train movements in yards.
Flangeway clearance refers to the open space maintained between running rails and check rails, not switch toe movement. Heel divergence describes the fixed separation distance at the rear end of the switch assembly rather than toe throw. Standard engineering terminology explicitly defines this lateral movement as the throw of the switch.
- Subject
- Engineering
- Category
- Civil Engineering
- Topic
- —
- Difficulty
- medium
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