distance traveled by a uniformly accelerated bike is given as

here we know that



now we will have from above equation


so it will cover the total distance of 300 m
 
        
             
        
        
        
Answer:
a)  Em₀ = 42.96 104 J
, b)    = -2.49 105 J
, c)  vf = 3.75 m / s
 = -2.49 105 J
, c)  vf = 3.75 m / s
Explanation:
The mechanical energy of a body is the sum of its kinetic energy plus the potential energies it has
         Em = K + U
a) Let's look for the initial mechanical energy
       Em₀ = K + U
       Em₀ = ½ m v2 + mg and
       Em₀ = ½ 50.0 (1.20 102) 2 + 50 9.8 142
       Em₀ = 36 104 + 6.96 104
       Em₀ = 42.96 104 J
b) The work of the friction force is equal to the change in the mechanical energy of the body
      = Em₂ -Em₀
 = Em₂ -Em₀
      Em₂ = K + U
      Em₂ = ½ m v₂² + m g y₂
      Em₂ = ½ 50 85 2 + 50 9.8 427
      Em₂ = 180.625 + 2.09 105
      Em₂ = 1,806 105 J
       = Em₂ -Em₀
 = Em₂ -Em₀
       = 1,806 105 - 4,296 105
 = 1,806 105 - 4,296 105
       = -2.49 105 J
 = -2.49 105 J
The negative sign indicates that the work that force and displacement have opposite directions
c) In this case the work of the friction going up is already calculated in part b and the work of the friction going down would be 1.5 that job
We have that the work of friction is equal to the change of mechanical energy
         = ΔEm
 = ΔEm
         = Emf - Emo
 = Emf - Emo
        -1.5 2.49 10⁵ = ½ m vf² - 42.96 10⁴
        ½ m vf² = -1.5 2.49 10⁵ + 4.296 10⁵
        ½ 50.0 vf² = 0.561
        vf = √ 0.561 25
       vf = 3.75 m / s
 
        
             
        
        
        
Answer: 
The electric field strength at the midpoint of the line joining the charges is zero (0)
Explanation:
Given that the two charges are both positive (same charge) and are equal in magnitude that is 6uC. The electric field strength at the midpoint of the line joining the two charges will be equal and opposite in magnitude, therefore they will cancel each other out and the electric field strength at this point will be equal to zero.
 
        
             
        
        
        
 A matchstick has a lot of chemical energy stored in it. When the match is struck, it burns and the chemical energy in it produces heat energy and light energy.
 
        
             
        
        
        
Plants in general I think. 
photosynthetic organisms.