By clicking the two-slit barrier and dragging it, you can change its position. Always allow a few seconds for the simulation to catch up with the changes you are making before analyzing the results. When the two-slit barrier is brought closer to the screen (and farther away from the source), what happens to the distance between two adjacent bright (or dark) fringes?

A. It becomes larger.

B. It becomes smaller.

C. It stays the same.

the answer the correct one is B

Explanation:

The interference phenomenon is described by

           d sin θ = m λ

The spectrum is recorded on a screen, so we can use trigonometry

          tan θ = y / L

In this experiment the angles are very small, so

           tan θ = sin θ /cos θ = sin θ

  We replace

         d y / L = m La m

        y = m Lam L / d

When the slits approach the screen the value of L decreases,

Therefore the value of the separation between the slits must also decrease

When reviewing the answer the correct one is B

force is based upon mass and acceleration.the statement is not always true.

it can be explained from newton's second law of motion.

as per newton's second law of motion the rate of change of momentum is directly proportional to the applied force and takes place along the direction of force.

mathematically it can be written as -

                                              ⇒      

here   k is the proportionality constant whose value is 1.

                                                            [a is the acceleration=dv/dt]

hence we see that force not only depends on mass and acceleration but also on velocity and rate of change of mass. force f will depend on mass and acceleration only when mass is constant.

hence the statement that force is based upon mass and acceleration is false.