Jia is preparing to cook a family dinner, and she begins by gathering ingredients for the main course and dessert. She realizes that most ingredients go through both physical and chemical changes as they cook.
As her family eats the delicious dinner, Jia remembers an important fact about the law of conservation of mass. What does she remember?
o A Matter always moves from hot to cold.
B. Matter is not created or destroyed in any change.
O C. Matter can change physically or chemically.
O D. Matter is the amount of mass in a given volume.

c. matter can change physically or chemically

Explanation:

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.