A 1.0 kg block and a 2.0 kg block are pressed together on a horizontal frictionless surface with a compressed spring between them. they are not attached to the spring. after they are released and have both moved free of the spring.
A. the magnitude of the momentum of the heavier block will be greater than the magnitude of the momentum of the lighter block.
B. the lighter block will have more kinetic energy than the heavier block.
C. both blocks will both have the same amount of kinetic energy.
D. both blocks will have equal speeds.
E. the heavier block will have more kinetic energy than the lighter block.

Two particles of masses m and 2m are placed on a smooth horizontal table. a string, which joins these two masses, hangs over the edge supporting a pulley, which suspends a particle of mass 3m.the pulley has negligible mass. the two parts of the string on the table are parallel and perpendicular to the edge of the table. the hanging parts of the string are vertical. find the acceleration of the particle of mass 3m.

Clothing made of several thin layers of fabric with trapped air in between, often called ski clothing, is commonly used in cold climates because it is light, fashionable, and a very effective thermal insulator. so it is no surprise that such clothing has largely replaced thickand heavy old-fashioned coats. (a) consider a jacket made of five layers of 0.1-mm-thick synthetic fabric (k = 0.13 w/m·°c) with 1.5-mm-thick air space (k = 0.026 w/m·°c) between the layers. assuming the inner surface temperature of the jacket to be 28°c and the surface area to be 1.25 m2, determine the rate of heat loss through the jacket when the temperature of the outdoors is 0°c and the heat transfer coefficient at the outer surface is 25 w/m2·°c. (b) what would your response be if the jacket is made of a single layer of 0.5-mm-thick synthetic fabric? what should be the thickness of a wool fabric (k = 0.035 w/m·°c) if the person is to achieve the same level of thermal comfort wearing a thick wool coat instead of a five-layer ski jacket?

The amount of work done is determined by 2 factors. describe an example of work (using the scientific definition) list the 2 factors that determine the amount of work done.