<span>When an object moves in a circle, the acceleration points toward the center of the circle. This acceleration is called centripetal acceleration.
We can use a simple equation to find centripetal acceleration.
a = v^2 / r
We can use this same equation to find the speed of the car.
v^2 = a * r
v = sqrt { a * r }
v = sqrt{ (1.50)(9.80 m/s^2)(11.0 m) }
v = 12.7 m/s
The speed of the roller coaster is 12.7 m/s</span>
The North Magnetic Pole is the point on the surface of Earth's Northern Hemisphere at which the planet's magnetic field points vertically downwards (in other words, if a magnetic compass needle is allowed to rotate about a horizontal axis, it will point straight down). There is only one location where this occurs, near (but distinct from) the Geographic North Pole and the Geomagnetic North Pole.
Answer: 
Explanation:
If we make an analysis of the net force 
of the rock that was thrown upwards, we will have the following:
(1)
Where:
is the force with which the rock was thrown
is the weight of the rock
Being the weight the relation between the mass 
of the rock and the acceleration due gravity 
:
(2)
(3)
Substituting (3) in (1):
(4)
(5) This is the net Force on the rock
On the other hand, we know this force is equal to the multiplication of the mass with the acceleration, according to Newton's 2nd Law:
(6)
Finding the acceleration 
:
(7)
(8)
Finally:
Gain in decibels is given by;
Gain db = 10*log (Po/Pi), where Po = Power output, Pin = Power input
Substituting;
Gain in db = 10 * log (50/5) = 10 db
