A roller coaster is traveling at 13 m/s when it approaches a hill that is 400 m long. Heading down the hill, it accelerates at 4.0 m/s2. What is the final velocity of the roller coaster?

The  value is    

Explanation:

From the question we are told that

   The initial  speed of the roller coaster is

    The  length of the hill is  

    The  acceleration of the  roller coaster is

Generally the acceleration is mathematically represented as

Here   is the initial time which is equal to zero

          is the final velocity which is mathematically represented as

So  

Solving this using quadratic formula we obtain

Generally  time cannot be negative so

Generally the  final velocity is mathematically represented as

c.the charges if the proton and electron and gravity

v=ir = 3x15 =45 v