The rear window defogger of a car consists of thirteen thin wires (resistivity 5 88.0 3 1028 V?m) embedded in the glass. The wires are connected in parallel to the 12.0-V battery, and each has a length of 1.30 m. The defogger can melt 2.10 3 1022 kg of ice at 0 8C into water at 0 8C in two minutes. Assume that all the power delivered to the wires is used immediately to melt the ice. Find the cross-sectional area of each wire.

Trajectories Flight paths through space Conic Sections Figure 8 (free return trajectories) Spiral (Electric propulsion solar sails) Suborbital trajectory Reach space, without completing a full orbit Example: For V2 with horizontal distance of 330 km, Δv = 1.6 km ≈ 3,580mph s Orbital Trajectories Kepler and Newton v = 2πr P v = GM √ r GM = 4π 22 r2 4π2 3 P = GM r Kepler’s 3rd law Video: https://www.youtube.com/watchv=Am7EwmxBAW8 Planet is one of foci of the orbit Fastest