Answer:
The work done to get you safely away from the test is 2.47 X 10⁴ J.
Explanation:
Given;
length of the rope, L = 70 ft
mass per unit length of the rope, μ = 2 lb/ft
your mass, W = 120 lbs
mass of the 70 ft rope = 2 lb/ft x 70 ft
= 140 lbs.
Total mass to be pulled to the helicopter, M = 120 lbs + 140 lbs
= 260 lbs
The work done is calculated from work-energy theorem as follows;
W = Mgh
where;
g is acceleration due gravity = 32.17 ft/s²
h is height the total mass is raised = length of the rope = 70 ft
W = 260 Lb x 32.17 ft/s² x 70 ft
W = 585494 lb.ft²/s²
1 lb.ft²/s² = 0.0421 J
W = 585494 lb.ft²/s² = 2.47 X 10⁴ J.
Therefore, the work done to get you safely away from the test is 2.47 X 10⁴ J.
Acceleration = (change of speed) / (time for the change)
Change in speed = (22 - 4) = 18 m/s.
Time for the change = 3 sec.
Acceleration = 18/3 = 6 m/s per second.
$34.75 per month
It is a trick question at the end because it says that anything over 250 kwh is $0.03. Although, you are only calculating for 180 kwh and the monthly charge.
You might just have to take a walk outside instead of a virtual one beside its healthier for you also what kind of area do you live in
Answer:
486,750 kg*m/s
Explanation:
Momentum is mass*velocity
M = m*v
M = 8850kg*55m/s
M = 486,750 kg*m/s