Consider a one-turn rectangular loop of wire placed in a uniform magnetic field as shown in the figure. The plane of the loop is perpendicular to the field lines. The resistance of the loop is $0.4\Omega$, and its inductance is negligible. The magnetic flux density (in Tesla) is a function of time, and is given by $B(t)=0.25 \sin \omega t$, where $\omega= 2\pi \times 50$ radian/second. The power absorbed (in Watt) by the loop from the magnetic field is _________.