The distance from one compression in a sound wave to the next compression is defined as the _________

What's the diameter of a dish antenna that will receive 10−20W of power from Voyager at this time? Assume that the radio transmi

Murrr4er [49]

Complete Question:

The Voyager 1 spacecraft is now beyond the outer reaches of our solar system, but earthbound scientists still receive data from the spacecraft s 20-W radio transmitter. Voyager is expected to continue transmitting until about 2025, when it will be some 25 billion km from Earth.

What s the diameter of a dish antenna that will receive 10−20W of power from Voyager at this time? Assume that the radio transmitter on Voyager transmits equally in all directions(isotropically). In fact, the antenna on Voyager focuses the signal in a beam aimed at the earth, so this problem over-estimates the size of the receiving dish needed.

Answer:

d = 2,236 m.

Explanation:

The received power on Earth, can be calculated as the product of the intensity (or power density) times the area that intercepts the power radiated.

As we assume that the transmitter antenna is ominidirectional, power is spreading out over a sphere with a radius equal to the distance to the source.

So, we can get the power density as follows:

I = P /A = P / 4*π*r², where P = 20 W, and r= 25 billion km = 25*10¹² m.

⇒ I = 20 W / 4*π* (25*10¹²)² m²

The received power, is just the product of this value times the area of the receiver antenna, which we assumed be a circle of diameter d:

Pr = I. Ar =( 20W / 4*π*(25*10¹²)² m²) * π * (d²/4) = 10⁻²⁰ W

Simplifying common terms, we can solve for d:

d= √(16*(25)²*10⁴/20) = 2,236 m.

3 0

3 years ago

Frame S' passes frame S in the usual way (positive directions). An object also moves in the positive direction. Which is true? T

lisov135 [29]

Answer:

The answer is "The object's speed relative to S can be greater than or less than its speed relative to S', depending on the actual values."

Explanation:

The S' frame and the object are moving in a positive direction. The object is moving with respect to the S frame so the S frame the rest frame

take the velocity of the object with respect to the rest frame as v and the velocity of the S' frame with respect S frame as v2

relative velocity of the object to the S' frame would be

Vrel = v2- v

This means the Vrel of the object with respect to the S' frame is less than the Vrel of the object with respect to the S frame

However is the S' velocity is greater than that of the object then the Vrel of the object with respect to the S' frame is greater than the Vrel of the object with respect to the S frame.

This would mean the second option is the answer, the relative speed of the object depends on the actual values.

3 0

3 years ago

A 1500 kg car traveling at 15.0 m/s to the south collides with a 4500 kg truck that is at rest at a stopligt. The car comes to a

Arlecino [84]

Answer:

Mathematically:

That will be

= 1500 x 15 x 4500

= 101,250,000

5 0

3 years ago

The accepted value for the density of iron is 7.87 g/cm3. a student records the mass of a 20.00 cm3 block of iron as 153.8 grams

dangina [55]

The density of an object can be calculated using the formula Density = Mass/Volume.

Experimental Density:

Density = 153.8g / 20.00 cm^3
Density = 7.69g/cm^3

Percent error equation:

% Error = | Theoretical Value - Experimental Value|/Theoretical Value * 100
% Error = | 7.87g/cm^3 - 7.69g/cm^3|/7.87g/cm^3 * 100
% Error = 2.29%

Therefore a is the correct answer.

6 0

3 years ago

What support system do you have in place to complete your scheduled exercises? How and why did you

Bingel [31]

Answer:

It has to be important to you.

-It has to be something that you are in control of.

-It has to be attainable, or able to be achieved.

-It has to be clear and specific.

-It has to have a plan.

Wellness

Wellness refers to a healthy state of being in body, mind, and emotion.

Body wellness

means eating right, exercising, and keeping your bodily systems in good health.

Mental wellness

means feeling safe and secure in your environment and at peace with your decisions and actions.

Emotional wellness

means feeling your best and having the ability to deal with many different situations.

Wellness: Setting Goals

The first step to setting a goal is defining it. Keep in mind that not everything you wish for can be a goal. When it comes to physical activity, diet, and exercise, you may wish to run a marathon before the end of the school year. However, this goal could be difficult to achieve if school ends in just a few months and you are not already training. A more reasonable goal might be to be able to run a mile in the amount of time considered healthy for your age group.

Importance of Physical Education

Physical education explores the methods, types, and benefits of physical activity for the body. In addition to staying active, making healthy choices about diet and exercise is important to overall personal and long-term health. Long-term health passed down through generations can also promote healthy family lifestyles.

Fitness

is the ability of the body to function effectively and efficiently during physical activity and is the ability to move joints through an entire range of motion.

Physical exercise

is the act of improving one's body through specific intentional movements.

differences between exercise and fitness

while anyone can exercise, only someone who exercises regularly can be fit.

Why is it important to make healthy choices about your diet and exercise?

Choosing healthy behaviors when it comes to diet and exercise is important to personal health, long-term health, and promoting healthy family lifestyles.

five components of physical education:

-Cardiorespiratory endurance

-Muscular strength

-Muscular endurance

-Flexibility

-Body composition

Explanation:

Life is WORTH LIVING

6 0

3 years ago

The distance from one compression in a sound wave to the next compression is defined as the __________.