An antenna array used in radio astronomy consists of a set of antennae equally-spaced along a north-south line. By reciprocity, the detection pattern of the antenna array is just the same as the radiation pattern as if the antennae were radiating at the same wavelength. The spacing between the antennae is smaller than the wavelength. Show that the array only receives radiation from a specific direction in the N-S plane, and that the direction can be chosen by int

Abicycle slows down when the rider applies the brakes. what type of energy transformation is involved in this example? a. kinetic energy into heat energy b. heat energy into potential energy c. potential energy into kinetic energy d. kinetic energy into mechanical energy

Ablock of mass m = 2.5 kg is attached to a spring with spring constant k = 740 n/m. it is initially at rest on an inclined plane that is at an angle of theta= 26 with respect to the horizontal, and the coefficient of kinetic friction between the block and the plane is uk = 0.17. in the initial position, where the spring is compressed by a distance of d = 0.16 m, the mass is at its lowest position and the spring is compressed the maximum amount. take the initial gravitational energy of the block as zero. the block's initial mechanical energy is 9.472 j.b. if the spring pushes the block up the incline, what distance l in meters will the block travel before coming to rest? the spring remains attached to both the block and the fixed wall throughout its motion.

Boiling water is an example of physical change. true or false