Here easy answer from online
In scientific contexts, mass is the amount of "matter" in an object (though "matter" may be difficult to define), whereas weight is the force exerted on an object by gravity.
Answer:
<em>K =400000 J</em>
Explanation:
<u>Kinetic Energy</u>
Is the energy an object has due to its state of motion. It's proportional to the square of the speed.
The equation for the kinetic energy is:

Where:
m = mass of the object
v = speed at which the object moves
The kinetic energy is expressed in Joules (J)
The car has a mass of m=2000 Kg and travels at v=20 m/s. Calculating the kinetic energy:

Calculating:
K =400000 J
Answer:
t = 0.33h = 1200s
x = 18.33 km
Explanation:
If the origin of coordinates is at the second car, you can write the following equations for both cars:
car 1:
(1)
xo = 10 km
v1 = 55km/h
car 2:
(2)
v2 = 85km/h
For a specific value of time t the positions of both cars are equal, that is, x=x'. You equal equations (1) and (2) and solve for t:


The position in which both cars coincides is:

30x30=900
The answer is 900 meters after 30 seconds