Explain why the mean and standard deviation are not appropriate for particle size distributions

1 answer:

8 0

The mean is the average of the sample data, while standard deviation is the average of the differences of each data to the mean. This could only be valid if there is a normal distribution. This distribution pertains to a bell-shaped frequency graph. However, in particle size distribution, the frequency of the sizes is rarely concentrated on the medium or middle size. It may be skewed to the left or skewed to the right. So, the mean and standard deviation is not a good measure for this type of distribution.

You might be interested in

You and your friends are playing tug of war. Your team pulls with a force of 55 N, to the right. The other team pulls with a for

Elza [17]

The net force is 10 n because it has 2 different forces that are not the same you must subtract them

4 0

3 years ago

Read 2 more answers

A water rocket has a mass of 0.8kg and is launched in a school playground with an inital upwards force of 12newtons. what is the

Darina [25.2K]

Weight = (mass) x (gravity).
It always acts downward.

On Earth, the acceleration of gravity is 9.807 m/s².
On the Moon, the acceleration of gravity is 1.623 m/s².

On Earth, the rocket's weight is (0.8kg) x (9.8 m/s²) = 7.84 newtons

On the Moon, the rocket's weight is (0.8kg) x (1.62 m/s²) = 1.3 newtons

The force of the rocket engine acts upward.
Its magnitude is 12 newtons. (From the burning chemicals.
Doesn't depend on local gravity. Same force everywhere.)

Now we have all the data we need to mash together and calculate the
answers to the question. You might choose a different method, but the
machine that I have selected to do the mashing with is Newton's 2nd law
of motion:

   Net Force = (mass) x (acceleration).

Since the question is asking for acceleration, let's first solve Newton's law
for it. Divide each side by (mass) and we have

   Acceleration = (net force) / (mass) .

On Earth, the forces on the rocket are

      (weight of 7.84 N down) + (blast of 12 N up) = 4.16 newtons UP (net)

   Acceleration = (4.16 newtons UP) / (0.8 kg) = 5.2 m/s² UP .

On the moon, the forces on the rocket are

   (weight of 1.3 N down) + (blast of 12 N up) = 10.7 newtons UP (net)

   Acceleration = (10.7 newtons UP) / (0.8 kg) = 13.375 m/s² UP

7 0

3 years ago

Which force is responsible for the formation of waves? A. gravity B. wind C. friction D. centripetal

notka56 [123]

Gravity is the cause of formation waves.

7 0

3 years ago

Read 2 more answers

a large cargo trucks needs to cross a bridge the truck is 30m long, and 3.2 wide, the cargo exerts a force of 54,000 N the bridg

otez555 [7]

Answer:

It isn't safe for the truck to cross the bridge because the pressure exerted by the truck on the bridge is greater than the maximum tolerable pressure for the bridge, 562.5 Pa > 450 Pa.

Explanation:

Pressure is expressed in Force/Area.

So, for the truck, force exerted = 54000 N

Area covered = 30 × 3.2 = 96 m²

Pressure exerted by the truck = 54000/96 = 562.5 Pa

The pressure exerted by the truck on the bridge is greater than the maximum tolerable pressure for the bridge, 562.5 > 450, hence, it isn't safe for the truck to cross the bridge.

5 0

4 years ago

A student is experimenting with some insulated copper wire and a power supply. She winds a single layer of the wire on a tube wi

OverLord2011 [107]

Answer:

$P=214.7187\,W$