There is NOT a difference in speed between a car going forwards at 5 m/s and a car moving backwards at 5 m/s.
Speed is just the rate of change of the position of an object. It is calculated by dividing the change in position (distance traveled) by the time it takes to move said distance.
The distance between the two points is always positive because the direction does not matter.
However, if we are looking for the velocity, the direction DOES matter. In this example, the velocity moving forwards is 5 m/s while the velocity moving backwards is -5 m/s.
In other words:
<em>Speed </em>is looking at the <em>magnitude</em>
<em>Velocity </em>is looking at the <em>magnitude </em><em>and </em><em>direction.</em>
 
        
             
        
        
        
Answer:
D. 
Explanation:
Solar energy is needed for photosynthesis, and chemical energy in the form of glucose is needed for cellular respiration.
 
        
             
        
        
        
The number of species on Earth tagged at 8.7 million as of 2011.
        
                    
             
        
        
        
Can you please add the choices?
 Thank you very much
        
                    
             
        
        
        
Species change over time. -The mechanism that produces the change is natural selection: the differential survival and reproduction of individuals based on variation in their traits. Natural selection acts on individuals but individuals do not evolve; their descendants do.