All categories

3 years ago

The first game in volleyball is played until a team reaches 25 points.

Physics

2 answers:

Zinaida [17]3 years ago

7 1

I don't understand this question

andreyandreev [35.5K]3 years ago

7 0

Answer: The answer to your question is true. Please mark me as brainliest!

You might be interested in

Psuedopod in a sentence

mixas84 [53]

Does it have to be that exact word. cause it is just another term for psuedopodium

5 0

3 years ago

A fan at a rock concert is 50.0 m from the stage, and at this point the sound intensity level is 114 dB. Sound is detected when

Marianna [84]

Answer:

A) $P=13.92\ J.s^{-1}$

B) $v=3730.9912\ m.s^{-1}$

C) $v=74.44\ mm.s^{-1}$

D) mosquitoes speed in part B is very much larger than that of part C.

Explanation:

Given:

Distance form the sound source, $s=50\ m$

sound intensity level at the given location, $\beta=114\ dB$

diameter of the eardrum membrane in humans, $d=8.4 \times 10^{-3}\ m$

We have the minimum detectable intensity to the human ears, $I_0=10^{-12}\ W.m^{-2}$

(A)

Now the intensity of the sound at the given location is related mathematically as:

$\beta=10\ log(\frac{I}{I_0} )$ ..........................................(1)

$114=10\ log\ (\frac{I}{10^{-12}} )$

$11.4=log\ I+12\ log\ 10$

$I=0.2512\ W.m^{-2}$

As we know :

$I=\frac{P}{A}$

$0.2512=\frac{P}{\pi\times \frac{8.4^2}{4} }$

$P=13.92\ J.s^{-1}$ is the energy transferred to the eardrums per second.

(B)

mass of mosquito, $m=2\times 10^{-6}\ kg$

Now the velocity of mosquito for the same kinetic energy:

$KE=\frac{1}{2} m.v^2$

$13.92=\frac{1}{2}\times 2\times 10^{-6}\times v^2$

$v=3730.9912\ m.s^{-1}$

(C)

Given:

Sound intensity, $\beta = 20\ dB$

Using eq. (1)

$20=10\ log\ (\frac{I}{10^{-12}} )$

$2=log\ I+12\ log\ 10$

$I=10^{-10}\ W.m^{-2}$

Now, power:

$P=I.A$

$P=10^{-10}\times \pi\times \frac{8.4^2}{4}$

$P=5.54\times 10^{-9}\ J.s^{-1}$

Hence:

$KE=\frac{1}{2} m.v^2$

$5.54\times 10^{-9}=0.5\times 2\times 10^{-6}\times v^2$

$v=0.07444\ m.s^{-1}$

$v=74.44\ mm.s^{-1}$

(D)

mosquitoes speed in part B is very much larger than that of part C.

7 0

3 years ago

Describe rotational motion

ratelena [41]

Rotational motion may be described analytically for bodies undergoing pure rotation.

3 0

3 years ago

A _______ is a repeating disturbance or vibration that transfers or moves energy from place to place without transporting mass.

Harman [31]

Answer: wave

Explanation:

These are the basic definitions and characteristic of the terms given, which show tha the only rigth answer is the second option: wave.

1) Force is an interaction. There are four natural forces: electrostatic, gravity, strong nuclear force and weak nuclear force.

2) Wave: is a sequence of pulses or vibrations that cause the continuous transportation of energy (propagation). There is not transport of mass, only energy.

Some examples of waves are sound waves, electromagnetic waves (light, radio waves, micro waves, infrarred waves, ultraviolet waves).

3) Vacuum: is the absence of matter; empty space. Only electromagnetic waves can travel through vacuum; other waves need a medium to travel.

4) Medium: any matter is a medium: a solid, the air, a liquid, all of them are media through which waves can transport its energy, depending of the wavelength.

3 0

3 years ago

Read 2 more answers

To make a ___________________ , position your car to the right side of the right lane

pashok25 [27]

A right turn would be the answer probably.

8 0

3 years ago

Read 2 more answers