A 23 kg child is riding a 6.7 kg bike with a velocity of 4.4 m/s to the northwest.

A round pipe of varying diameter carries petroleum from a wellhead to a refinery. At the wellhead, the pipe's diameter is 50.9 c

seraphim [82]

Answer:

Flow rate 2.34 m3/s

Diameter 0.754 m

Explanation:

Assuming steady flow, the volume flow rate along the pipe will always be constant, and equals to the product of flow speed and cross-section area.

The area at the well head is

$A = \pi r_w^2 = \pi (0.509/2)^2 = 0.203 m^2$

So the volume flow rate along the pipe is

$\dot{V} = Av = 0.203 * 11.5 = 2.34 m^3/s$

We can use the similar logic to find the cross-section area at the refinery

$A_r = \dot{V}/v_r = 2.34 / 5.25 = 0.446 m^2$

The radius of the pipe at the refinery is:

$A_r = \pi r^2$

$r^2 =A_r/\pi = 0.446/\pi = 0.141$

$r = \sqrt{0.141} = 0.377m$

So the diameter is twice the radius = 0.38*2 = 0.754m

6 0

3 years ago

An automobile travels on a straight road for 40 km at 30 km/h. It then continues in the same direction for another 40 km at 60 k

Butoxors [25]

Answer:

The average velocity is 40km/h.

Explanation:

The average velocity is $\bar{v}=\frac{\Delta x }{\Delta t}$ , where $\Delta x$ is the distance traveled and $\Delta t$ the time elapsed.

The distance traveled is clearly 80km since it's all done in the same direction, we only need to know the time elapsed. For this we calculate the time elapsed on the first part, and add it to the time elapsed on the second part using always the formula $\Delta t=\frac{\Delta x }{v}$ , where v is the velocity on each part, which is constant.

The time elapsed for the first part is $\Delta t_1=\frac{40 km}{30km/h}=\frac{4}{3}h$ , and the time elapsed for the second part is $\Delta t_2=\frac{40 km}{60km/h}=\frac{2}{3}h$ , giving us a total time of $\Delta t_1+\Delta t_2=\frac{4}{3}h+\frac{2}{3}h$ =2h.

Finally, we can calculate the average velocity: $\bar{v}=\frac{80km}{2h}=40km/h$ .

6 0

3 years ago

There are four coils of wire being used as electromagnets. They all have the same size and are made up of the same material but

bonufazy [111]

Answer:

The coil with the maximum number of loops will produce the magnetic field with the maximum strength.

Explanation:

The magnetic field produced by a current-carrying coil at a point on the axis which is passing through its center and perpendicular to its plane is given by

$\rm B=\dfrac{\mu_o N I }{2}\ \dfrac{R^2}{(r^2+R^2)^{3/2}}.$

<em>where</em>,

$\mu_o$ = magnetic permeability of the free space.
N = number of loops of the coil.
I = current flowing through the coil.
R = radius of the coil.
r = distance of the point where the magnetic field is to be found from the center of the coil.

Now, it is given that all the four coils have the same size, means same radius R, same material, means same permeability for all the coils, and the same amount of current is passing through all the coils, means same current I.

The magnetic field of all the four coils is differing only due to the number of loops N.

Thus, the coil with the maximum number of loops N will produce the magnetic field with the maximum strength.

4 0

4 years ago

I need help on this which is correct? plz help me its timed.

mario62 [17]

Answer:

Watershed should be your answer!

3 0

3 years ago

A car driving down the road speeds up to pass bus. While passing changed velocity from 10 m/s to 35 m/s in 5 seconds. What is th

VMariaS [17]

Answer:

The ans is 3

Explanation:

First write the given values and write the formula of acceleration than do velocity - final velocity by time taken is 10-35%5 so, therefore acceleration of car is 3

5 0

3 years ago