Solution :
From the given data,
For the spherical shell is 
where x is the radius of gyration and the acceleration of a rolling body on an inclined plane = a
Therefore,



= 0.6 x 9.81 x sin ( 29.7)




Δt = 1.411 s
Explanation:
Let h is the height of the plane above ground. x is the horizontal distance between the ground and the airport. Let s(t) is the distance between the plane and the airport. So,
...........(1)
Given, h = 4, x = 40 and s(t) = -20 mph
Differentiate equation (1) wrt t


When x = 40, 



So, the speed of the airplane is 241.14 m/s. Hence, this is the required solution.
Answer:
doubled
Explanation:
F=ma1----------(1)
2F = ma2-------(2)
Divide 2nd equation by 1st one
we get a1×2=a2
Mass of object/source
Gravity
Fg=mg