where Î '' is the elastic modulus ; stress is the force that causes the deformation divided by the area to which the force is applied ; and strain is the ratio of the change caused by the stress to the original state of the object . where lambda ( Î '' ) is the elastic modulus ; stress is the restoring force caused due to the deformation divided by the area to which the force is applied ; and strain is the ratio of the change caused by the stress to the original state of the object .