At the same instant that a 0.50-kg ball is dropped from 25 m above earth, a second ball, with a mass of 0.25 kg, is thrown straight upward from earth's surface with an initial speed of 15 m/s. they move along nearby lines and pass without colliding. at the end of 2.0 s the acceleration of the center of mass of the two-ball system is? a 4.0-n puck is traveling at 3.0 m/s. it strikes an 8.0-n puck, which is stationary. the two pucks stick together. their common final speed is?

The ballistic pendulum was invented in 1742 by english mathematician benjamin robins. it consists of an initially stationary pendulum that moves after being struck by a bullet, and it is used to measure the original velocity of the bullet. the known variables are the bullet's mass m, the pendulum's mass m, and the height to which the block and bullet swing, determined by the length of the pendulum l and final angle θ. two principles of physics are necessary to solve for the bullet's original velocity. what are these principles? conservation of momentum and newton's third law conservation of energy and conservation of angular momentum grade summary deductions 0% potential 100% conservation of momentum and newton's second law. newton's second law and conservation of angular momentum. conservation of energy and newton's third law conservation of momentum and conservation of angular momentum. conservation of momentum and conservation of energy conservation of energy and newton's second law.

Write the equation for momentum, first using symbols for the variables, then using words for the variables.

Two resistors r1 and r2 may be connected either in series or parallel across an ideal battery with emf ε. we desire the rate of energy dissipation of the parallel combination to be 8.75 times that of the series combination. if r1 = 105 ω, what are the (a) smaller and (b) larger of the two values of r2 that result in that dissipation rate?