A soccer ball takes 20 s to roll 10 m.
Speed of the soccer ball
= 10/20 m/s = 1/2 m/s
        
             
        
        
        
Answer:
hey did you complete the whole test?
Explanation:
 
        
             
        
        
        
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.
Learn more about speed here: brainly.com/question/6504879
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Answer:
It requires evidence or proof and to avail something is true.
Explanation: