Once a falling object has reached a constant velocity, the object
a. stops accelerating
b. stops speeding up
c. experiences equal forces of gravity and air resistance
d. all of the above

The energy released by a chemical reaction can be measured using a calorimeter. when barium hydroxide octahydrate crystals are reacted with dry ammonium chloride inside of a coffee cup calorimeter, the temperature of the 18.00 g of water in the calorimeter decreases from 30.0°c to 8.0°c. the equation for calculating energy absorbed or released by a reaction is: where q is the energy released or absorbed, m is the mass of water in the calorimeter, cp is the specific heat of water, and δt is the observed temperature change. if the specific heat of liquid water is 4.19 j/g·°c, how much energy was absorbed by the reaction?

Consider two less-than-desirable options. in the first you are driving 30 mph and crash head-on into an identical car also going 30 mph. in the second option you are driving 30 mph and crash head-on into a stationary brick wall. in neither case does your car bounce off the thing it hits, and the collision time is the same in both cases. which of these two situations would result in the greatest impact force?

Atoy airplane, flying in a horizontal, circularpath, completes 10. complete circles in 30.seconds. if the radius of the plane’s circular pathis 4.0 meters, the average speed of the airplane is(1) 0.13 m/s (3) 1.3 m/s(2) 0.84 m/s (4) 8.4 m/s