One direction of the emerging paradigm of interface design is the use of physical metaphors, the adoption of physical phenomenon from the real world with physical principles such as gravity or inertia. To explore effectiveness of physical metaphors in interaction design, we conducted an exploratory study by selecting one specific task where a physical metaphor was applied with physics: searching for a phone number in a contact list using an inertial scroll method with a mouse and touch screen interface environment. The result from this initial study showed that employing a physical metaphor does not always guarantee an improvement of performance; a different effect can be drawn according to the interaction style. Keywords Physical metaphor, interaction design, interface design, interaction styles, inertial scroll ACM Classification Keywords H5.2. [Information interfaces and presentation]: User Interfaces Copyright is held by the author/owner(s). CHI 2009, April 4?9, 2009, Boston, Mass...