A1000 kg car is moving south with a speed of 20 m/s. what is the momentum of the car? ?

20000kg*m/s south

Explanation: Momentum is defined as the amount of movement, and it can be described by the equaton:

P = m*v

Where P is the momentum, m is the mass of the object and v is the velocity.

You can notice that the velocity is a vector (so it has a direction) and also is the momentum (it also has a direction, the same one as the velocity)

so if we have that the velocity is 20m/s south (v is a vector, so i will use south as the direction of the vector), and the mass is 1000kg, the momentum is:

P = 1000kg*20m/s south = 20000kg*m/s south

freezing

deposition

condensation

explanation;

melting also called fusion is the process where solid becomes liquid, sublimation is the process where solid becomes gaseous without first changing to liquid, deposition involves change from gaseous to solid state, freezing involves change from liquid to solid, boiling or evaporation involves change of liquid to gaseous state, while condensation is the change from gaseous state to liquid state.

endothermic reactions involves absorption of heat from the surroundings or the environment while exothermic reactions involves loss of heat energy to the surroundings.

in this case, sublimation, evaporation and melting are endothermic reactions (gain energy from the environment) while, freezing, deposition and condensation are exothermic (loss of energy to the surroundings) reactions.

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.