Answer:
Force, F = 187.42 N
Explanation:
It is given that,
Mass of boy, m = 30 kg
Acceleration due to gravity, 
Radius of curvature of the roller coaster, r = 15 m
Speed of the car, v = 7.3 m/s
The force acting on the boy are force of gravity and the centripetal force. The net force acting on him is as follows :



F = 187.42 N
So, he press against the seat with a force is 187.42 N. Hence, this is the required solution.
To solve this problem we will use the definition of the period in a simple pendulum, which warns that it is dependent on its length and gravity as follows:

Here,
L = Length
g = Acceleration due to gravity
We can realize that
is a constant so it is proportional to the square root of its length over its gravity,

Since the body is in constant free fall, that is, a point where gravity tends to be zero:

The value of the period will tend to infinity. This indicates that the pendulum will no longer oscillate because both the pendulum and the point to which it is attached are in free fall.
Only the tiny command module survives to return to Earth. The Saturn V rocket's first stage carries 203,400 gallons (770,000 liters) of kerosene fuel and 318,000 gallons (1.2 million liters) of liquid oxygen needed for combustion
Answer:
physical science
earth science and life science
Einstein's theory of General Relativity states that space-time is able to be warped in the presence of mass or energy. This warping is what "tells" matter how to move in its presence. In the paraphrased words of physicist John Wheeler, matter tells space-time how to warp, and warped space-time tells matter how to move.