A tetrahedron has an equilateral triangle base with 20-cm-long edges and three equilateral triangle sides. The base is parallel to the ground, and a vertical uniform electric field of strength 200 N/C passes upward through the tetrahedron.
What is the electric flux through the base?

electric flux through the base is 3.45 m²/C

Explanation:

given data

base length = 20 cm

uniform electric field of strength = 200 N/C

solution

as base is perpendicular to filed flux through the base

Ф = - × E × a² .......................1

here E is strength of electric field and a is side

so put here value in equation 1 we get

Ф = - × 200 × 0.20²

Ф =  3.45 m²/C

so electric flux through the base is 3.45 m²/C

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.