Answer:
(a) Time t = 16.46 sec
(b) Time t =13.466 sec
(c) Deceleration = 
Explanation:
(a) As the train starts from rest its initial velocity u = 0 m/sec
Acceleration 
Final speed v = 80 km/hr

From first equation of motion v =u+at
So 
(b) Now initial speed u = 22.22 m/sec
As finally train comes to rest so final speed v=0 m/sec
Deceleration 
So 
(c) We have given that initial velocity = 80 km/hr = 22.22 m/sec
Final velocity v = 0 m/sec
Time t = 8.30 sec
So acceleration is given by

As acceleration is negative so it is a deceleration
<span> d = r*t is the basic distance equation
d = 6000 km
t with the tail wind = 6 hr
r with the tail wind = speed of the plane + wind speed = s + w
t with the head wind = 7.5 hr
r with the head wind = speed of the plane - wind speed = s-w
(s+w)*6 = 6000
(s-w)*7.5 = 6000
s + w = 1000
s - w = 800
</span><span> 2s = 1800
s = 900 km/h
s + w = 1000
w = 100
Check the anwer by calculating the return trip.
(900-100) * 7.5 = 800 * 7.5
800 * 7.5 = 6000 km
Answer: The rate of the jet in still air is 900 km/h. The rate of the wind is 100 km/hr.</span>
The approximate amount of thrust(force) you need to apply to the lander to
keep its velocity roughly constant is zero.
<h3>What is Newton's second law of motion?</h3>
Newton's second law of motion states that the acceleration the force acting
on the object is directly proportional to its rate of change of momentum.
F = m a
If the object is moving with uniform velocity, it simply means that the
acceleration is zero, and the corresponding force will also be zero.
Read more about Constant velocity here brainly.com/question/3052539
The answer is D. the way I remember it is they all end with -alism.
Answer:
Vb = k Q / r r <R
Vb = k q / R³ (R² - r²) r >R
Explanation:
The electic potential is defined by
ΔV = - ∫ E .ds
We calculate the potential in the line of the electric pipe, therefore the scalar product reduces the algebraic product
VB - VA = - ∫ E dr
Let's substitute every equation they give us and we find out
r> R
Va = - ∫ (k Q / r²) dr
-Va = - k Q (- 1 / r)
We evaluate with it Va = 0 for r = infinity
Vb = k Q / r r <R
We perform the calculation of the power with the expression of the electric field that they give us
Vb = - int (kQ / R3 r) dr
We integrate and evaluate from the starting point r = R to the final point r <R
Vb = ∫kq / R³ r dr
Vb = k q / R³ (R² - r²)
This is the electric field in the whole space, the places of interest are r = 0, r = R and r = infinity