Aluminium foil with all metallic items, aluminium foil reacts to being placed in a microwave oven. This is because of the electromagnetic fields of the microwaves inducing electric currents in the foil and high potentials at the sharp points of the foil sheet; if the potential is sufficiently high, it will cause electric arcing to areas with lower potential, even to the air surrounding the sheet. Modern microwave ovens have been designed to prevent damage to the cavity magnetron tube from microwave energy reflection, and aluminium packages designed for microwave heating are available. Heavier foils made of aluminium are used for art,
Bruce foil a downwards force. Bruce foils can be mounted in pairs, one on each side, as used in some trimaran designs. In this case, the leeward foil works in conjunction with the leeward ama to provide lift, and the windward foil can be retracted to reduce drag. At equilibrium, the force from the foil and the sail will always be balanced, so capsize should be impossible, but in practice that is not the case. Since the foil's force is relative to the hull's movement through the water, and the sail's force is relative to the wind moving past the sail, sudden