Answer:
Density relates a mass to its volume.
Density varies with temperature
Density determines if a substance floats or sinks.
Density may have units of grams per milliliter (g/mL)
Explanation:
Density
is a characteristic property of a substance or material and is defined as the relationship between the mass
of a body or substance and the volume
it occupies:
This means the density is inversely proportional to the volume.
On the other hand, density is a scalar quantity and according to the International System of Units its unit is
, although it can be also expressed in
.
It should be noted that the density of a body is related to its buoyancy, a substance or body will float on another fluid if its density is lower. In addition, if the pressure of the substance remains constant, as the temperature increases, the density decreases; this means density varies with the temperature as well.
Answer:
none it's Hydroelectric energy
Answer:
just before landing the ground
Explanation:
Let the velocity of projection is u and the angle of projection is 30°.
Let T is the time of flight and R is the horizontal distance traveled. As there is no force acting in horizontal direction, so the horizontal velocity remains constant. Let the particle hits the ground with velocity v.
initial horizontal component of velocity, ux = u Cos 30
initial vertical component of velocity, uy = u Sin 30
Time of flight is given by

Final horizontal component of velocity, vx = ux = u Cos 30
Let vy is teh final vertical component of velocity.
Use first equation of motion
vy = uy - gT


vy = - u Sin 30
The magnitude of final velocity is given by


v = u
Thus, the velocity is same as it just reaches the ground.