Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
Concepts Of Physics MCQ Edition [Volume 1]PhysicsWave Motion and Waves on a String

A pulse travelling on a string is described by the function y = a^3 (x - vt)^2 + a^2 , where a = 5 mm and v = 20 cm s ⁻¹ . Taking x = 0 at the middle of the string, determine the positions of the peak of the pulse at t = 0 , 1 s , and 2 s respectively.

Options

  1. Ax = 0 , x = 10 cm , and x = 20 cm
  2. Bx = 0 , x = 20 cm , and x = 40 cm
  3. Cx = 5 mm , x = 20 cm , and x = 40 cm
  4. Dx = 0 , x = -20 cm , and x = -40 cm

Correct answer

B. x = 0 , x = 20 cm , and x = 40 cm

Step-by-step solution

The equation of the pulse is y = a^3 (x - vt)^2 + a^2 . The peak of the pulse occurs where the displacement y is maximum. This happens when the denominator is minimum, which corresponds to (x - vt)^2 = 0 . Thus, the position of the peak at any time t is given by x = vt . Given the velocity of the pulse v = 20 cm s ⁻¹ . At t = 0 , the position of the peak is x = 20 0 = 0 . At t = 1 s , the position of the peak is x = 20 1 = 20 cm . At t = 2 s , the position of the peak is x = 20 2 = 40 cm .

Practice Wave Motion and Waves on a String on Quantrex Academy →

More from Wave Motion and Waves on a String

A wave pulse travelling on a string at a speed of 40 cm s ⁻¹ in the negative x -direction has its maximum located at x = 0 when t = 0 . Where will this maximum be found at t = 5 s A wave travelling on a string stretched along the X -axis has an equation given by y = A , e^ - ( x a + t T )^2 . Identify the direction in which the wave is travelling.A wave travelling on a string stretched along the X -axis has an equation given by y = A , e^ - ( x a + t T )^2 . Locate the maximum of the pulse at t = T and at t = 2T respectivelA wave travelling on a string stretched along the X -axis has an equation given by y = A , e^ - ( x a + t T )^2 . Determine the dimensions of A , a , and T .A wave travelling on a string stretched along the X -axis has an equation given by y = A , e^ - ( x a + t T )^2 . Compute the wave speed.A stretched string carries a wave in the positive x -direction with a wave speed of v . The displacement of the particle at x = 0 is described by f(t) = A (t/T) . Determine the wavThe figure displays a wave pulse at t = 0 . The pulse travels to the right with a speed of 10 cm s ⁻¹ . Determine the respective rightward shifts of the shape of the string at t = A wave pulse travels on a string towards the positive X -axis with a speed v . At t = 0 , the shape of the string is given by g(x) = A (x/a) , where A and a are constants. Write th Full Wave Motion and Waves on a String list All Concepts Of Physics MCQ Edition [Volume 1] PYQs