Kecepatan benda sebagai fungsi waktu dinyatakan oleh v=(2t3-3t2)m/s bila t dalam sekon dan posisi awal 4m. maka posisi saat t=2s adalah

Which of the following correctly describes what happens when an atomic bomb explodes? small pieces of fissionable material are joined and form a body with a mass greater than the critical mass, the relative number of neutrons escaping decreases, and a chain reaction and explosion result. large pieces of fissionable matter are brought together quickly and form a body with a mass smaller than the critical mass, the relative number of escaping neutrons increases, and a chain reaction and explosion result.