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3 years ago

True or false? All waves need a medium in order to travel

2 answers:

4 0

That's false. Mechanical waves (like sound and ocean waves) do
need a medium to travel in, but electromagnetic waves (like radio
and light) don't.

Pavlova-9 [17]3 years ago

3 0

That is false because electromagnetic waves can travel without a medium.

hope this helps :)

You might be interested in

When work is done on an object, where does the energy used to do the work go?

borishaifa [10]

-- If the work is done to make the object move faster, then
the work done becomes kinetic energy of the object.

-- If work is done on the object but it doesn't move any faster,
then there must be friction holding it back. In that case, the work
that's done just to keep the object moving becomes heat, in the
places where the friction acts on it.

3 0

3 years ago

A capacitor with a very large capacitance is in series with a capacitor that has a very small capacitance. what can we say about

Misha Larkins [42]

A capacitor with a very large capacitance is in series with a capacitor
that has a very small capacitance.

The capacitance of the series combination is slightly smaller than the
capacitance of the small capacitor. (choice-C)

The capacitance of a series combination is

1 / (1/A + 1/B + 1/C + 1/D + .....) .

If you wisk, fold, knead, and mash that expression for a while,
you find that for only two capacitors in series, (or 2 resistors or
two inductors in parallel), the combination is

(product of the 2 individuals) / (sum of the individuals) .

In this problem, we have a humongous one and a tiny one.
Let's call them 1000 and 1 .
Then the series combination is

(1000 x 1) / (1000 + 1)

= (1000) / (1001)

= 0.999 000 999 . . .

which is smaller than the smaller individual.

It'll always be that way.

5 0

3 years ago

Which of the following is the equation for calculating daily caloric needs? A. BMR calories + Digestion calories B. BMR calories

labwork [276]

Explanation:

To determine your total daily calorie needs, multiply your BMR by the appropriate activity factor, as follows: If you are sedentary (little or no exercise) : Calorie-Calculation = BMR x 1.2. If you are lightly active (light exercise/sports 1-3 days/week) : Calorie-Calculation = BMR x 1.375.

HAPPY TO HELP

8 0

2 years ago

Read 2 more answers

A soccer player kicks a rock horizontally off a 37 m high cliff into a pool of water. If the player hears the sound of the splas

Alchen [17]

<h2>Answer:</h2>

(a). 16.741 m/s

(b). 15.75 m/s

<h2>Explanation:</h2>

In the question,

Height of the cliff, h = 37 m

Time taken to reach the sound to us = 2.92 s

Speed of the sound in air at room temperature = 343 m/s

Now,

Let us say the speed of the ball = u m/s

So,

Time taken by the ball to reach at the bottom, t is given by,

$t=\sqrt{\frac{2h}{g}}\\t=\sqrt{\frac{2\times 37}{9.8}}\\t=2.747\,s$

So,

Splash is heard after = 2.92 s

So,

Time taken by sound to travel the shortest distance along the hypotenuse of the triangle thus formed is,

t = 2.92 - 2.747

t = 0.172 s

Now,

Distance traveled by sound is given by,

$Distance=343\times 0.172\\Distance=59.02\,m$

So,

In the triangle using the Pythagoras Theorem,

Horizontal distance traveled is,

$D=\sqrt{59.02^{2}-37^{2}}\\D=45.99\,m$

So,

Speed of throwing of ball is given by,

$Distance=Speed\times Time\\45.99=u\times 2.747\\u=16.741\,m/s$

Therefore, the speed of the ball = 16.741 m/s.

(b).

If,

Speed of sound = 331 m/s

So,

Distance traveled by sound is,

$Distance=331\times 0.172\\Distance=56.932\,m$

So,

Distance traveled in the horizontal by ball is,

$Distance=\sqrt{56.932^{2}-37^{2}}\\Distance=43.269\,m$

So,

Speed of the ball thrown is given by,

$Speed=\frac{Distance}{Time}\\Speed=\frac{43.269}{2.747}\\Speed=15.75\,m/s$

Therefore, the speed of the ball = 15.75 m/s.

8 0

3 years ago

Chord progressions that move to resting points that release tension are called

Sav [38]

Cadences.

These cadences are the resulting tensions that chords release from their resting points. This movement is classified from a unstable chord progression to a stable one. Thank you for your question. Please don't hesitate to ask in Brainly your queries.

6 0

2 years ago