A toy race track has a 1.0-m-long straight section connected to a vertical circular loop-the-loop section of radius 15 cm. The straight section has a uniform magnetic field directed upward of magnitude 0.10 T and contains two metal strips with negligible resistance. The toy car has mass 40 g and contains a 2.0-cm-long perpendicular rod with resistance 100 m Ω that connects the strips when placed on the track. With a toy car placed on the starting line, a dc voltage is applied to the strips and the cars accelerate along the straight portion of the track. The operation is similar to that of a rail gun. Ignoring friction, what minimum voltage must be applied to the strips for a toy car to make it around the loop-the-loop section without losing contact with the track?