"a hypothetical pendulum suspended by a weightless frictionless thread of constant length"@en-us . "0"^^ . . "0"^^ . "104060164"@en-us . . . "103339806"@en-us . . "104221673"^^ . . "simple pendulum"@en-us . . . "simple pendulum"^^ . . . "04221673-n"^^ .