Study the scenario.
an object is at rest. at five seconds, someone comes over and pushes the object forward with a force of 10 n.
which of the following choices describes the force needed to keep the object in static equilibrium?
1. a force of 10 n must be exerted in a backward direction on the box at any time after five seconds so that the forces are balanced and the object moves at a constant velocity.
2. a force greater than 10 n must be exerted in a forward direction on the object at exactly five seconds to prevent the object from moving.
3. a backward force of 10 n must be exerted on the box at exactly 10 seconds so that the forces are balanced and the object remains at rest.
4. there is no way to keep the object in static equilibrium once a force has been exerted on it.

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?

Apebble is thrown into a calm lake, ripples are formed from the center and move outward. the water particles in the lake travel in a circular pattern that moves up and down on the surface of a lake, and the energy travels a) diagonally. b) downward. c) horizontally. d) upward.

What is the temperature in degrees celsius of a substance with a tempature of 49k