Answer:
Drag; water.
Explanation:
Friction can be defined as a force that resists the relative motion of two objects when there surface comes in contact. Thus, it prevents two surface from easily sliding over or slipping across one another. Also, friction usually reduces the efficiency and mechanical advantage of machines but can be reduced through lubrication.
Generally, there are four (4) main types of friction and these includes;
I. Static friction.
II. Rolling friction.
III. Sliding friction.
IV. Fluid friction.
Fluid friction can be defined as a type of friction that acts on physical objects moving through a liquid or gas. A fluid refers to any physical substance that can flow and is able to take the shape of a container.
In science, matter can be defined as anything that has mass and occupies space. Any physical object that is found on earth is typically composed of matter. Matter are known to be made up of atoms and as a result has the property of existing in states.
Basically, matter exists in three (3) distinct or classical phases and these are; solid, liquid and gas.
Generally, friction applies to all states of matter; in the gaseous state, it is called drag resistance and in a liquid it's called water resistance.
The water and solutes the first enters the nephron tubules undergo a process just before it exits the body as a urine. This process is called filtration. It operates when 20 percent of the solution volume is filtered in the renal corpuscle at a given time. It is reportedly stated that there are around 180 liters of this fluid being filtered by the kidney every day.
Answer:
Explanation:
18 km / h
= 300 m / min
12 km / h = 200 m / min
distance travelled in 200 minutes = 300 x 200 = 60000 m
distance travelled in 50 minute in return journey = 200 x 50 = 10000 m
total distance travelled = 70000 m
total time = 250 minute
speed = 70000 / 250
= 280 m / min
= 16.8 km / h
Total displacement = 60000 - 10000 = 50000 m
total time = 250 min
velocity = 50000 / 250
= 200 m / min
= 12 km / h
Answer:
I₂ = I₀ 1/4
Explanation:
For this exercise we use the definition of intensity which is the power per unit area
I = P / A
The emitted power is constant, so
P = I A
We can write this equation for the start and end point with index 2
I₀ A₀ = I₂ A₂
I₂ = I₀ A₀ / A₂
The spot area is the area of the circle
A₀ = π r₀²
We substitute
I₂ = I₀ r₀² / r₂²
It indicates that the radius of the spot is twice the initial radius
r₂ = 2 r₀
I₂ = I₀ (r₀ / 2 r₀)²
I₂ = I₀ 1/4
Answer:
Acceleration of the train is -3 m/s²
Explanation:
Since it stops,
final velocity (v) = 0 m/s
time (t) = 25 seconds
initial velocity(u) = 75 m/s
Now,
accelereation = (v-u)/t
or, a = (0-75)/25
or, a = -75/25
so, a = -3 m/s²