An object of mass \( 'm' \) initially at rest on a smooth horizontal plane starts moving under the action of force \( F = 2 \, N \). In the process of its linear motion, the angle \( \theta \) (as shown in figure) between the direction of force and horizontal varies as \( \theta = kx \), where \( k \) is a constant and \( x \) is the distance covered by the object from its initial position. The expression of kinetic energy of the object will be \( E = \dfrac{n}{k} \sin \theta \). The value of \( n \) is ___________.
