The same 2000 kg truck formerly traveling at 32 m/s, plows into a brick wall and comes to rest in 0.5 seconds. Determine the size of the
force the rock wall exerts on the car.

How much work would a child do while puling a 12-kg wagon a distance of 3m with a 22 n force directed 30 degrees with respect to the horizontal? (a) 82j (b) 52j (c) 109j (d) 95j

The speed of sound in ice, water, and steam is shown. what best explains the speed of sound in different states of matter? sound travels fastest in ice because energy is easier to transfer when the molecules are close together. sound travels slowest in steam because the sound has to move around the gas molecules that are far apart. sound travels fastest in ice because the temperature of solids is always greater, so the heat transfers the sound energy. sound travels slowest in steam because the pressure is so great the sound cannot travel though the steam particles.

Give one example to show that when substances are mixed, it may result in a chemical or a physical change depending on the conditions.