Answer:
the signs of heat and work are; -Q and -W
Explanation:
The first law of thermodynamics is given by; ΔU = Q − W
where;
ΔU is the change in internal energy of a system,
Q is the net heat transfer (the sum of all heat transfer into and out of the system)
W is the net work done (the sum of all work done on or by the system).
Now, The system in this case is the tire and since the air gets warmer, heat must have left the system. Therefore Q is negative (-Q).
Since work is done by the system, W remains negative.
Thus, the signs of heat and work are; -Q and - W
Force of 500 N is acting on the parachutist.
Parachutist applies 500 N force in downward direction.
Answer:
300 N upward
Solution:
Parachutist feels air resistance of 800 N.
Thus, 800 N of force is acting in upward direction.
Total force acting on the parachutist is given by,
= air resistance force - force of parachutist
= 800-500
= 300 N
Direction of force is in upward direction because the air resistance force is more than force of parachutist.
Answer:
A. respiration.
Explanation:
Cellular respiration can be defined as a series of metabolic reactions that typically occur in cells so as to produce energy in the form of adenosine triphosphate (ATP). During cellular respiration, high energy intermediates are created that can then be oxidized to make adenosine triphosphate (ATP). Therefore, the intermediary products are produced at the glycolysis and citric acid cycle stage.
Additionally, mitochondria provides all the energy required in the cell by transforming energy forms through series of chemical reactions; breaking down of glucose into Adenosine Triphosphate (ATP) used for providing energy for cellular activities in the body of living organisms.
Basically, oxygen goes into the body of a living organism such as plants, humans and animals when they breathe while glucose is absorbed by the body when they eat.
Hence, the conversion of sugar to energy in the presence of oxygen is respiration.