Answer:
The average velocity is 180 km/hr
Explanation:
Given;
initial velocity, u = 60 km per hour
final velocity, v = 120 km per hour
initial time = 1 hour
final time = 2 hour
Initial position = 60 km/h x 1 hour = 60 km
final position = 120 km/h x 2 hour = 240 km
The average velocity is given by;

Therefore, the average velocity is 180 km/hr
The answer is True - but Powell was borrowing from Winston Churchill who originally used this quote to describe Tact.
Work is considered as the Force performed on a body to move it a certain distance, that is
W = Fd
Here
W = Work
F = Force
d = Distance
In this case we have the values of work and distance, therefore clearing for the Force we would have to

Replacing,


Therefore the force that Marissa must exert on the windows shade is 0.4N
Answer:
Please check the attached file for the derivation
Explanation:
Check the attached file
Answer:
Dx/dt = 4,8 f/s
Explanation:
The ladder placed against a wall, and the ground formed a right triangle
with x and h the legs and L the hypothenuse
Then
L² = x² + h² (1)
L = 26 f
Taking differentials on both sides of the equation we get
0 = 2x Dx/dt + 2h Dh/dt (1)
In this equation
x = 10 distance between the bottom of the ladder and the when we need to find, the rate of the ladder moving away from the wall
Dx/dt is the rate we are looking for
h = ? The height of the ladder when x = 10
As L² = x² + h²
h² = L² - x²
h² = (26)² - (10)²
h² = 676 - 100
h² = 576
h = 24 f
Then equation (1)
0 = 2x Dx/dt + 2h Dh/dt
2xDx/dt = - 2h Dh/dt
10 Dx/dt = - 24 ( -2 ) ( Note the movement of the ladder is downwards)
Dx/dt = 48/10
Dx/dt = 4,8 f/s