The speed of the roller coater at the bottom of the hill is 31 m/s.
<h3>
Speed of the roller coater at the bottom of the hill</h3>
Apply the principle of conservation of mechanical energy as follows;
K.E(bottom) = P.E(top)
¹/₂mv² = mgh
v² = 2gh
v = √2gh
where;
- v is the speed of the coater at bottom hill
- h is the height of the hill
- g is acceleration due to gravity
v = √(2 x 9.8 x 49)
v = 31 m/s
Thus, the speed of the roller coater at the bottom of the hill is 31 m/s.
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Answer:
Reflection of sound waves also leads to echoes. Echoes are different than reverberations. Echoes occur when a reflected sound wave reaches the ear more than 0.1 seconds after the original sound wave was heard. ... Reflection of sound waves off of curved surfaces leads to a more interesting phenomenon.
 
        
             
        
        
        
The answer is having fewer neutrons than protons or electrons.
        
                    
             
        
        
        
HIV can be contracted from contact with bloodborne pathogens.
Other bloodborne diseases are HBV, malaria, syphilis and brucellosis
<h3>What are bloodborne pathogens?</h3>
Bloodborne pathogens can be defined as those microorganisms or pathogenic organisms that cause disease and are present in human blood.
Blood borne pathogens can also be contacted through the following means
- Se- xual contact
- Needle contact
In conclusion; HIV can be contracted from contact with bloodborne pathogens.
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