Answer:
230.4 s
Explanation:
The speed of car A is

and the distance travelled is

so the time taken for car A is

The speed of car B is

and the distance travelled is

so the time taken for car B is

So the difference in time is

Which corresponds to

so car B arrived 230.4 s before car A.
Answer:
This is because the acceleration of objects due to gravity is independent of the mass of the object and is constant for all objects, therefore, all objects fall with the same speed.
Explanation:
The weight of an object or force of gravity acting on an object on the surface of earth is a product of its mass and acceleration due to gravity.
Mathematically, w = mg
where, m=mass of the object; g = acceleration due to gravity
Also, from newton's law of gravitation, gravitational force on the object ,F = GMm/r²
where G is the gravitational constant; M is mass of Earth; m is mass of object; r is the distance of separation between the object and the center of mass of the earth which is approximately the radius of earth.
Since the weight of an object is equal to the force of gravitation acting on it
W = F
mg = GMm/r²
g = GM/r²
The expression above is that of the relationship between the force of gravity acting on a body on the earth's surface, the weight of that body and the acceleration due to gravity, g.
It can be seen that the acceleration due to gravity g is independent of the mass of the object. Therefore, the acceleration of objects due to gravity is constant for all objects and all objects fall with the same speed.
Answer:
heat came from the supernova that led to the formation of solar system
We want to know what does the fact that Mercury has no atmosphere tell us. Since Mercury has no atmosphere it cant reflect a lot of sunlight that is hitting its surface. Its constantly being hit by solar wind. So Mercury reflects a small percentage of the sunlight that strikes it.