All categories

3 years ago

If a typical smelt weighs 225 g, what is the total mass of pcbs in a smelt in the great lakes?

1 answer:

8 0

Since a typical smelt has 1.04 ppm of PCB is great lakes. So the amount of PCB in a smelt in great leak can be calculated by multiplying the mass of smelt by the pcbs present in a smelt

225 g * ( 1.04/100000) = 2.34 x10^-4 g pcbs

You might be interested in

Definition of waves

Dmitriy789 [7]

Answer:

A wave can be described as a disturbance that travels through a medium from one location to another location.

Explanation:

6 0

3 years ago

A car is moving in the positive direction along a straight highway and accelerates at a constant rate while going from point A t

rusak2 [61]

Answer:

The time where the avergae speed equals the instaneous speed is T/2

Explanation:

The velocity of the car is:

v(t) = v0 + at

Where v0 is the initial speed and a is the constant acceleration.

Let's find the average speed. This is given integrating the velocity from 0 to T and dividing by T:

$v_{ave} = \frac{1}{T}\int\limits^T_0 {v(t)} \, dt$

v_ave = v0+a(T/2)

We can esaily note that when t=T/2

v(T/2)=v_ave

Now we want to know where the car should be, the osition of the car is:

$x(t) = x_A + v_0 t + \frac{1}{2}at^2$

Where x_A is the position of point A. Therefore, the car will be at:

x(T/2) = x_A + v_0 (T/2) + (1/8)aT^2

8 0

3 years ago

A Rankine cycle with one closed feedwater heater with its drain cascaded backward has a water mass flow rate through the steam g

mamaluj [8]

Answer:Draw a T-s diagram for the ideal Rankine Cycle

Explanation:

6 0

3 years ago

A boy jumps from rest, straight down from the top of a cliff. He falls halfway down to the water below in 0.866 s. How much time

Iteru [2.4K]

<h2>Entire trip takes 1.22 seconds.</h2>

Explanation:

We have equation of motion s = ut + 0.5 at²

Initial velocity, u = 0 m/s

Acceleration, a = 9.81 m/s²

Time, t = 0.866 s

Substituting

s = ut + 0.5 at²

s = 0 x 0.866 + 0.5 x 9.81 x 0.866²

s = 3.68 m

Halfway is 3.68 m

Total height = 2 x 3.68 = 7.36 m

We have equation of motion s = ut + 0.5 at²

Initial velocity, u = 0 m/s

Acceleration, a = 9.81 m/s²

Time, t = ?

Displacement, s = 7.36 m

Substituting

s = ut + 0.5 at²

7.36 = 0 x t + 0.5 x 9.81 x t²

t = 1.22 s

Entire trip takes 1.22 seconds.

7 0

3 years ago

If a girl carries groceries up a flight of stairs, is she doing work on the groceries? Explain.

nikdorinn [45]

Answer:

Explanation:

Yes she is doing work. With or without the groceries, she is still doing work. She does more work with the groceries than without because Work is defined by F which is defined by mass. The mass increases with the groceries.

The work done is against the force of gravity.

4 0

3 years ago