Greg drew a diagram to compare two of the fundamental forces.

A venn diagram of 2 intersecting circles with the left circle labeled gravitational force and the right circle labeled electromagnetic force. There is an X in the gravitational force circle. There is a Z in the electromagnetic force circle. There is a Y in the intersecting area.
Which labels belong in the areas marked X, Y, and Z?

X: Attractive
Y: Repulsive
Z: Infinite range
X: Infinite range
Y: Attractive
Z: Repulsive
X: Always attractive
Y: Infinite range
Z: Attractive or repulsive
X: Attractive or repulsive
Y: Infinite range
Z: Always attractive

4

explanation:

4

-4 on

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.

  the unit of the measure =

explanation:

  the property that is quantified by the energy needed per of material to raise the temperature by one.

  si unit of energy = joule (j)

  si unit of temperature = kelvin (k)

  si unit of mass of material = kilogram (kg)

the property that is quantified by the energy needed per of material to raise the temperature by one is called specific heat.

the unit of specific heat is