A block sliding along a horizontal frictionless surface with speed v collides with a spring and compresses it by 1.0 cm . What will be the compression if the same block collides with the spring at a speed of 4v

Respuesta :

Answer:

The  compression is  [tex]x = 0.05 \ m[/tex]

Explanation:

From the question we are told that

     The first velocity is  v

     The  compression of the spring is  [tex]d = 1.0 \ cm = 0.01 \ m[/tex]

      The  second velocity is  4v

Generally according to the law of  energy conservation

   The  kinetic energy of the block is equal to the energy stored in the spring that is  

       [tex]\frac{1}{2} * m* v^ 2 = \frac{1}{2} * k * d^2[/tex]

For  first speed

      [tex]m* v^ 2 = k * 0.01^2[/tex]

=>   [tex]m* v^ 2 = k * 0.0001[/tex]

=>  [tex]k = \frac{ m v^2 }{ 0.0001}[/tex]

For second  speed

       [tex]\frac{1}{2} * m* (5v)^ 2 = \frac{1}{2} * k * x^2[/tex]

=>    [tex]12.5mv^2 = 0.5 k x^2[/tex]

substituting for k

=>    [tex]12.5mv^2 = 0.5 (\frac{mv^2}{0.0001} ) x^2[/tex]

=> [tex]12.5 = 5000x^2[/tex]

=>  [tex]x = 0.05 \ m[/tex]