According to one embodiment, a sensor includes a base body including a first face, a first support portion, a first movable portion, and a first insulating member. The first face includes a first base region, a second base region, and a third base region. The first support portion is fixed to the third base region. The first movable portion is supported by the first support portion. The first movable portion includes a first movable region and a second movable region. A first gap is provided between the first base region and the first movable region. The first insulating member is fixed to the second base region, and located between the second base region and the second movable region in a first direction from the third base region to the first support portion. A second gap is provided between the first insulating member and the second movable region.