Two gliders collide on an air track. Glider 1 has a mass of 7.0 kg, and glider 2 has a mass of 4.0 kg. Before the collision, glider 1 had a velocity of 2.0 m/s, and glider 2 had a velocity of -5.0 m/s. If the collision is perfectly elastic, what is the total kinetic energy of both gliders after the collision?

Suppose that 27 j of work is needed to stretch a spring from its natural length of 6 m to a length of 9 m. (a) how much work is needed to stretch the spring from 12 m to 14 m? j (b) how far beyond its natural length will a force of 78 n keep the spring stretched?

What causes the development of most clouds and precipitation in the atmosphere?

Consider each of the electric- and magnetic-field orientations given next. in each case, what is the direction of propagation of the wave? a)\vec ein the +xdirection,\vec bin the +ydirection. choose+ x direction- x direction+ y direction- y direction+ z direction- z direction b)\vec ein the -y direction,\vec bin the +x choose+ x direction- x direction+ y direction- y direction+ z direction- z direction c)\vec ein the +z direction,\vec bin the -x direction. choose+ x direction- x direction+ y direction- y direction+ z direction- z direction d)\vec ein the +y direction,\vec bin the -z direction. choose+ x direction- x direction+ y direction- y direction+ z direction- z direction