Answer:

Explanation:
Force can be found by multiplying the mass by the acceleration.

The mass of the roller coaster is 2000 kilograms and the acceleration is 2 meters per second squared.

Substitute the values into the formula.

Multiply.

- 1 kg*m/s² is equal to 1 N
- Therefore our answer of 4000 kg*m/s² is equal to 4000 Newtons

The net force acting on the roller coaster is <u>4000 Newtons.</u>
I think the question meant to say net force on the box. Since force is a vector, the direction matters. 20N left is negated completely by the 50N right, which means the net force is 50N-20N to the right, 30N.
The coefficient of kinetic friction<span> is the force between two objects when one object is moving, or if two objects are moving against each other</span>
Answer:
Classification of the Elements. These three groups are: metals, nonmetals, and inert gases.
Explanation:
1) The total mechanical energy of the rock is:

where U is the gravitational potential energy and K the kinetic energy.
Initially, the kinetic energy is zero (because the rock starts from rest, so its speed is zero), and the total mechanical energy of the rock is just gravitational potential energy. This is equal to

where

is the mass,

is the gravitational acceleration and

is the height.
Putting the numbers in, we find the potential energy

2) Just before hitting the ground, the potential energy U is zero (because now h=0), and all the potential energy of the rock converted into kinetic energy, which is equal to:

where v is the speed of the rock just before hitting the ground. Since the mechanical energy of the rock must be conserved, then the kinetic energy K before hitting the ground must be equal to the initial potential energy U of the rock:

3) For the work-energy theorem, the work W done by the gravitational force on the rock is equal to the variation of kinetic energy of the rock, which is: