A35 kg box is pulled with a rope from above at an angle of 20. the box begins to move when f 200n. calculate the frictional force acting on the box. calculate the normal force acting on the box.

b) 188 N

c) 275 N

Explanation:

Draw a free body diagram of the box.  There are four forces:

Applied force F at an angle θ

Weight mg pulling down

Normal force Fn pushing up

Friction force Ff pushing left

(b)

Sum of the forces in the x direction:

∑F = ma

F cos θ − Ff = 0

Ff = F cos θ

Ff = 200 cos 20°

Ff = 188 N

(c)

Sum of the forces in the y direction:

∑F = ma

F sin θ + Fn − mg = 0

Fn = mg − F sin θ

Fn = (35)(9.8) − 200 sin 20°

Fn = 275 N

if you answer my question i will answer yours

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.