Answer:
t = 1.068 s
Step-by-step explanation:
given,
a(t) =- k v(t)
speed of the object decreases from 800 ft/s to 700 ft/s
distance = 1400 ft
time for deceleration = ?
a(t) =- k v(t)


integrating both side


..........(1)
since,



![1400= -\dfrac{800}{k}[e^{-kt}-e^0]](https://tex.z-dn.net/?f=1400%3D%20-%5Cdfrac%7B800%7D%7Bk%7D%5Be%5E%7B-kt%7D-e%5E0%5D)
from equation 1
![k= -\dfrac{8}{14}[\dfrac{7}{8}-1]](https://tex.z-dn.net/?f=k%3D%20-%5Cdfrac%7B8%7D%7B14%7D%5B%5Cdfrac%7B7%7D%7B8%7D-1%5D)

putting value of k in equation (1)

t = 1.068 s
The measure of angle A is 55°.
Solution:
Let us take B be the adjacent angle of 145°.
<em>Sum of the adjacent angles in a straight line = 180°</em>
⇒ m∠B + 145° = 180°
Subtract 145° from both sides.
⇒ m∠B + 145° - 145° = 180° - 145°
⇒ m∠B = 35°
The adjacent angle of 145° is 35°.
In the image, angle B and angle A equal to 90°.
⇒ m∠B + m∠A = 90°
⇒ 35° + m∠A = 90°
Subtract 35° from both sides.
⇒ m∠A = 55°
The measure of angle A is 55°.
Answer: 15.9
Step-by-step explanation: