A beam is pivoted at one end, as shown.

An AM radio station broadcasts isotropically (equally in all directions) with an average power of 3.80 kW. A receiving antenna 7

Alecsey [184]

Answer:0.1759 v

Explanation:

Intensity of wave at receiver end is

I= $\frac{P_{avg}}{A}$

I= $\frac{3.80\times 10^3}{4\times \pi \times \left ( 4\times 1609.34\right )^2}$

I= $7.296\times 10^{-6} W/m^2$

Amplitude of electric field at receiver end

$E_{max}=\sqrt{2I\mu _0c}$

Amplitude of induced emf

= $E_{max}d$

= $\sqrt{2\times 7.29\times 10-6\times 4\pi \times 3\times 10^8}\times 0.75$

= $17.591\times 10^{-2}=0.1759 v$

7 0

3 years ago

block with of mass m is at rest on horizontal frictionless surface at time t=0. A force given by F=Bt+C is applied horizontally

Alexeev081 [22]

Answer:

$v_{2} =\frac{1}{2}$

Explanation:

From the second law of Newton movement laws, we have:

$F=m*a$ , and we know that a is the acceleration, which definition is:

$a=\frac{dv}{dt}$ , so:

$F=m*\frac{dv}{dt}\\\frac{dv}{dt}=\frac{F}{m}=\frac{\frac{1}{2}(t+1)}{4}=\frac{t+1}{8}$

The next step is separate variables and integrate (the limits are at this way because at t=0 the block was at rest (v=0):

$dv=\frac{1}{8}(t+1)dt\\\int\limits^{v_{2}}_0 \, dv=\int\limits^{2}_{0} {\frac{1}{8}(t+1)} \, dt$

$v_{2}=\frac{1}{8}*(\frac{t^{2}}{2}+t)$ (This is the indefinite integral), the definite one is:

$v_{2}=\frac{1}{8}*(2+2)=\frac{1}{2}$

3 0

3 years ago

What is cosmic background radiation?

Kobotan [32]

Cosmic background radiation is electromagnetic radiation from the sky with no discernible source. The origin of this radiation depends on the region of the spectrum that is observed.

6 0

3 years ago

Read 2 more answers

DESCRIBE floods and droughts. What are their effects? EXPLAIN how they can be prevented

BabaBlast [244]

Answer:

<u>EFFECTS: ( doughts)</u>

There would be less water in the river for you and other people who live along the river to use.
If we use too much water during times of normal rainfall, we might not have enough water when a drought happens.

<u>EFFECTS:( FLOODS)</u>

The immediate impacts of flooding include loss of human life, damage to property, destruction of crops, loss of livestock, and deterioration of health conditions owing to waterborne diseases.
power plants, roads and bridges are damaged and disrupted, some economic activities may come to a standstill, people are forced to leave their homes and normal life is disrupted.

How to prevent from flooding is :

Construct buildings above flood levels.
Tackle climate change

How to prevent from droughts :

drought trends that may occur based on statistical and actual weather forecasts.
In the U.S., the U.S. Drought Monitor provides a day-by-day visual of the drought conditions around the country.

* Hopefully this helps:) Mark me the brainliest:)!!!

~234483279c20~

3 0

3 years ago

Ex 10: My dog runs at 6 m/s for 18 meters. How long did she run for?

Hunter-Best [27]

She ran for 3s

Put 18/6 because in order to find how long she ran for you need to divide the distance by the meters ran, once you do that you will get 3.

7 0

3 years ago