in a young's double-slit experiment the center of a bright fringe occurs wherever waves from the slits differ in the distance they travel by a multiple of

The path difference will be zero.

Explanation:

Given that,

In a young's double-slit experiment the center of a bright fringe occurs wherever waves from the slits differ in the distance.

Suppose, we find the multiple of wavelength

In young's double slit experiment,

We need to calculate the multiple of wavelength

Using formula of path difference

....(I)

Where, m = fringe number

= wavelength

For center of a bright fringe ,

m = 0

Put the value into the formula

Put the value in equation (I)

Hence, The path difference will be zero.

answer: the exterior temperature of commercial jet planes as they leave the stratosphere and return to the ground increases steadily.

explanation:

the lower most layer of atmosphere is troposphere which extends from 0 to 12 km above the surface of the earth. the temperature initially decreases as distance is increased from the earth's surface. commercial jets fly in lower part of the stratosphere. the stratosphere extends upto 50 km. the temperature in stratosphere starts rising again due to presence of ozone which traps the uv rays.

thus, when the planes leave the stratosphere and return to the ground, the exterior temperature increases steadily.