Manipulate the equation "v=d/t" to find the answers to these problems using

Am example of a mechanical wave is?

Bogdan [553]

An example of a mechanical wave is a sound wave

3 0

4 years ago

A bicycle tire rotates 25 times in 10 seconds. What is it’s average angular velocity?

ryzh [129]

<h2>Answer:</h2>

<u>Angular velocity of bicycle tire is 15.78 radians per second.</u>

<h3>Explanation:</h3>

Angular velocity is the change in angular speed of an object with respect to time take for change or it is the rate of change of circular motion.

In the given question the circular displacement is 25 rounds around a central point.

The angular displacement is measured in degrees and 1 round is equal to 360 degrees.

25 Rounds = 25 × 360 = 9000 degrees.

Angular velocity = angular displacement /time = 9000/10 = 900 degrees per second.

In SI,angular velocity is represented in radians per second.

So, 1 radian = 57.29 degrees

Angular velocity = 15.78 radians per second

3 0

3 years ago

(II) A 1200-kg car moving on a horizontal surface has speed v = 85 km/h when it strikes a horizontal coiled spring and is brough

Pie

Answer:

k = 138440 N/m

Explanation:

given,

Mass of the car = 1200 Kg

speed of the car = 85 km/h

= 85 x 0.278 = 23.63 m/s

KE of the car

$KE = \dfrac{1}{2} mv^2$

Using Spring Energy Formula

$KE_{spring}=\dfrac{1}{2}kx^2$

Using conservation of energy

$\dfrac{1}{2} mv^2=\dfrac{1}{2}kx^2$

$k = \dfrac{mv^2}{x^2}$

$k = \dfrac{1200\times 23.63^2}{2.2^2}$

k = 138440 N/m

Spring stiffness constant of the spring is equal to k = 138440 N/m

7 0

3 years ago

A 4812 kg boulder sits on top of a 203 m cliff. What is its PE?

Bond [772]

Answer:

Explanation:

The potential energy of a body can be found by using the formula

PE = mgh

where

m is the mass

h is the height

g is the acceleration due to gravity which is 9.8 m/s²

From the question we have

PE = 4812 × 9.8 × 203

We have the final answer as

Hope this helps you

7 0

3 years ago

Loudspeakers can produce intense sounds with surprisingly small energy input in spite of their low efficiencies. Calculate the p

Dennis_Churaev [7]

Answer:

$5.87*10^{-4}W$

Explanation:

Given that:

$\beta = 89,6 dB$

$D = 13.0 cm$

$r = \frac{D}{2}\\ = \frac{13.0}{2}\\ = 6.5 cm\\=0.065m$

Efficiency = 2.06 % = 0.0206

The intensity level of sound is given by the formula:

$\beta = (10dB) log (\frac{I}{I_o} )$

$\frac{\beta}{(10dB) } =log (\frac{I}{I_o} )$

Taking their exponential; we have :

$10^{\frac{\beta}{10dB}}= \frac{I}{I_o}$

$I = I_o(10^{\frac{\beta}{10dB}})$

Replacing our values; we have:

$I = (10^{-12}W/m^2)(10^{\frac{89.6}{10dB}})$

$= 9.12 *10^{-4}W/m^2$

Power Output;

$P_{out} = IA\\P_{out}=I(\pi r^2)\\P_{out}=(9.12*10^{-4}W/m^2)(3.14)(0.065m)^2\\P_{out}=1.2099048*10^{-5} W$

The power output that is required to produce a 89.6 dB sound intensity level for a 13.0 cm diameter speaker that has an efficiency of 2.06% is;

$P_{in}= \frac{P_{out}}{0.0206}$

$P_{in}= \frac{{1.2099048*10^{-5}}}{0.0206}$

$P_{in}= 5.87*10^{-4}W$

Therefore, The power output that is required to produce a 89.6 dB sound intensity level for a 13.0 cm diameter speaker that has an efficiency of 2.06% is $5.87*10^{-4}W$

8 0

3 years ago