Answer:
Speed of physicist car is 0.036c or 1.08 x 10⁷ m/s .
Explanation:
Doppler Effect is defined as the change in frequency or wavelength of the wave as the source or/and observer moving away or towards each other.
In this case, the Doppler effect equation in terms of wavelength is :
......(1)
Here
is source wavelength,
is observed wavelength, v is speed of the observer and c is the speed of light.
Given :
Source wavelength,
= 660 nm = 660 x 10⁻⁹ m
Observed wavelength,
= 555 nm = 555 x 10⁻⁹ m
Substitute these values in the equation (1).






v = 1.08 x 10⁷ m/s
The question is incomplete. Here is the complete question.
Three crtaes with various contents are pulled by a force Fpull=3615N across a horizontal, frictionless roller-conveyor system.The group pf boxes accelerates at 1.516m/s2 to the right. Between each adjacent pair of boxes is a force meter that measures the magnitude of the tension in the connecting rope. Between the box of mass m1 and the box of mass m2, the force meter reads F12=1387N. Between the box of mass m2 and box of mass m3, the force meter reads F23=2304N. Assume that the ropes and force meters are massless.
(a) What is the total mass of the three boxes?
(b) What is the mass of each box?
Answer: (a) Total mass = 2384.5kg;
(b) m1 = 915kg;
m2 = 605kg;
m3 = 864.5kg;
Explanation: The image of the boxes is described in the picture below.
(a) The system is moving at a constant acceleration and with a force Fpull. Using Newton's 2nd Law:




Total mass of the system of boxes is 2384.5kg.
(b) For each mass, analyse each box and make them each a free-body diagram.
<u>For </u>
<u>:</u>
The only force acting On the
box is force of tension between 1 and 2 and as all the system is moving at a same acceleration.


= 915kg
<u>For </u>
<u>:</u>
There are two forces acting on
: tension caused by box 1 and tension caused by box 3. Positive referential is to the right (because it's the movement's direction), so force caused by 1 is opposing force caused by 3:


= 605kg
<u>For </u>
<u>:</u>


= 864.5kg
Answer:
D. Less rain and snow.
Explanation:
A factor that can be a account for a drop in the water table is, less rain and snow. to topography, water tables is influenced by lot of factors, including the geology, weather, ground cover.
The correct is 72 watt
We know that formula of power is 
so putting the value of Voltage and Resistance in Formula of power so we get

What is Power?
Electric power is the rate at which an electric circuit transfers electrical energy per unit time.
Typically, electricity is generated by generators, but it can also be supplied by sources such as electric batteries. The electric power industry typically distributes it via an electric power grid to businesses and homes (as domestic mains electricity).
Transmission lines allow electric power to be delivered over long distances and used for high-efficiency applications such as motion, light, or heat. Electric charges are converted to other forms of energy when they pass through an electric potential difference (voltage).
To learn more about Power from the given link:
brainly.com/question/2333114
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