Here is a more detailed explanation:
The force of gravity acting on an object is given by the equation:
```
F = mg
```
where:
* F is the force of gravity in newtons (N)
* m is the mass of the object in kilograms (kg)
* g is the acceleration due to gravity (9.8 m/s^2)
The acceleration of an object due to gravity is also given by the equation:
```
a = g
```
where:
* a is the acceleration of the object in m/s^2
* g is the acceleration due to gravity (9.8 m/s^2)
As the roller coaster goes down a hill, the force of gravity acting on it will cause it to accelerate. This acceleration will cause the roller coaster's speed to increase. As the roller coaster goes up a hill, the force of gravity acting on it will cause it to decelerate. This deceleration will cause the roller coaster's speed to decrease.
The overall time for the roller coaster trip will be the same, regardless of the mass of the roller coaster. This is because the force of gravity acting on the roller coaster is constant, and the acceleration of the roller coaster due to gravity is also constant.
