According to one embodiment, a sensor includes a base including a first face including a first face region, and a first structure body fixed to the first face region. The first structure body includes a first support portion fixed to the first face region, a second support portion fixed to the first face region, a first movable portion, and a first fixed electrode fixed to the first face region. The first movable portion is supported by the first and second support portions and apart from the base in a first direction crossing the first face region. The first movable portion includes a first movable electrode facing the first fixed electrode, and a first conductive member. A first current flows the first conductive member along a second direction crossing the first direction. A first gap is provided between the first fixed electrode and the first movable portion.