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.
Time t = ?
<span>When wave is moving from
y = 0 to y =12 cm</span>
By using the formula,
y = 15cos [(π/12) t)] =
0,
cos [(π/12) t)] = 0 =
cos (π/2), so,
(π/12)t = π/2,
t = (π/2) (12/π)
t = 12/2
<span>t = 6 sec</span>
<span>so 6 sec is the least amount of time required</span>
When dealing with the force of gravity between two objects, there are only two things that are important – mass, and distance. The force of gravity depends directly upon the masses of the two objects, and inversely on the square of the distance between them.
Answer:
Sounds cool.. but what do they do?
Explanation:
Geostrophic winds blows parallel to the isobars. That is because the Coriolis force and pressure gradient force ( PGF ) are in balance. But near the surface the friction can act to change the direction of the wind and to slow it down. Coriolis force decreases at the surface and PGF stays the same. The difference in terrain conditions affects how much friction is exerted. Hills and forests force the wind to change direction more than flat areas. Answer: Friction reduces the speed so Coriolis is weakened.
