The 9 kg block is then released and accelerates to the right, toward the 5 kg block. The surface is rough and the coefficient of friction between each block and the surface is 0.4 . The two blocks collide, stick together, and move to the right. Remember that the spring is not attached to the 9 kg block. Find the speed of the 9 kg block just before it collides with the 5 kg block. Answer in units of m/s

Complete Question

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The velocity is    

Explanation:

The kinetic energy of the 9 kg can be determined by these expression

        Kinetic energy of 9 kg  block = initial energy stored - energy lost as a result of friction

  Now to obtain the initial energy stored

               Let U denote the initial energy stored and

                     

Where x  is the length the spring is displaced

k is the force constant of the string

         

         

   Now referring to the formula above

i.e          Kinetic energy of 9 kg  block = initial energy stored - energy lost as a result of friction

               

               

               

and we are told that coefficient of friction  = 0.4 and the mass is 9 kg ,the acceleration due to gravity  this displacement length of spring = 0.6

  Therefore  

                             

           

Ithink the answers is b i hope it my friend message me if i’m wrong and i’ll change my answer and fix it for you

Answer: it will take   4.36 seconds to reach her average velocity 10.69 miles/hour.explanation:   we have equation of motion ,where s is the displacement, a is the acceleration, u is the initial velocity and t is the time taken.average velocity = displacement/ time taken.average velocity = 10.69 miles/hr = 10.69*1.6*1000/(60*60) = 4.75 m/s4.75 = s/ts = 4. 1we also have acceleration = 2.18 m/s², initial velocity = 0 m/sso it will take   4.36 seconds to reach her average velocity 10.69 miles/hour.