According to one embodiment, a sensor a sensor includes a base, a first support portion fixed to the base, and a first movable portion supported by the first support portion. The first movable portion includes first and second movable base portions, a connecting base portion, first and second movable beams, and first and second movable conductive portions. The first movable beam includes a first beam end portion, a first beam other end portion, and a first beam intermediate portion. The second movable beam includes a second beam end portion, a second beam other end portion, and a second beam intermediate portion. The first movable conductive portion includes a first crossing conductive portion, a first extending conductive portion, and a first other extending conductive portion. The second movable conductive portion includes a second crossing conductive portion, a second extending conductive portion, and a second other extending conductive portion.