Given the time of flight for a projectile fired horizontally was o.66 seconds, and it landed 3: 3 m from where it was launched, the projectile's muzzle velocity was: (a) 0.20 m/s, (b) 0.22 m/s, (c) 0.50 m/s, (d) 5.0 m/s, (e) none of the above.

Option (D)

Explanation:

In the projectile motion

Horizontal distance = horizontal velocity × time

3.3 = u × 0.66

u = 5 m/s

Muzzle velocity is 5 m/s

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.