Based on the given description above about the metal that is being used for fractures, the old metal coating that was used before was made of TIN, and now, the metal that is used to repair fractures in order to avoid further corrosion is ALUMINUM. Hope this answer helps.
Solution:
a) We know acceleration due to gravity, g = GM/r²
Differential change, dg/dr = -2GM/r³
Here, r = 50*Rh = 50*2GM/c² = 100GM/c
²
My height, h=dr = 1.7 m
Difference in gravitational acceleration between my head and my feet, dg = -10 m/s²
or, dg/dr = -10/1.7 = -2GM/(100GM/c²)³
or, 5.9*100³*G²*M² = 2c⁶
or, M = 0.59*c³/(1000G) = 2.39*1032 kg = [(2.39*1032)/(1.99*1030 )]Ms = 120*Ms
Mass of black hole which we can tolerate at the given distance is 120 time the mass of Sun.
b) This limit an upper limit ,we can tolerate smaller masses only.
Equilibrium refers to a state in which all of the external forces on an object all balance each other such that there is no net effect (net force equals 0). An object in equilibrium will not experience acceleration, and will either remain at rest, or continue moving at a constant velocity. Here's a simple example, pick up a book (or any random object) and hold it up in the air. The book is now in equilibrium, the downwards force of gravity is perfectly countered by the upwards force that you are applying to it. Notice that the object neither falls nor goes upwards (i.e. no acceleration). Now let go of the book, notice how it falls downwards till it hits the ground (or whatever was beneath it). That is because without the upwards force applied by your hand, the object is no longer in equilibrium, and the force of gravity takes over until it is in equilibrium again.
We calculate the difference between the two velocities,
135 km/h - 35 km/h = 100 km/h
Then, convert the difference into units of m/s
100 km/h x (1000 m/ 1 km) x (1 hour / 3600 s) = 27.78 m/s
Then divide the difference by time.
acceleration = 27.78 m/s / 10.5 s = 2.65 m/s²
(2) In terms of g,
x = 2.65 / 9.80 = 0.27
Therefore, the answer would be,
a = 0.27g
