I do not know where to start.

A sound with an intensity greater than_____ dB can cause damage to human ears.

sergiy2304 [10]

85 decibels or higher can cause damage to the human ear. Decibels is the value of the measurement of sound. Hearing loss can be caused by noise coming from a loud sound. Noise induced hearing loss maybe permanent loss or temporary loss. Examples of activities that can give you a noise induced hearing loss is target shooting, listening to music in your earphones that have a high volume, and using lawnmowers.

5 0

4 years ago

A 0.14-MIN baseball is dropped from rest. It has a momentum of 0.90 kg⋅m/skg⋅m/s just before it lands on the ground.

nikitadnepr [17]

The time spent in the air by the ball at the given momentum is 6.43 s.

The given parameters;

<em>momentum of the ball, P = 0.9 kgm/s</em>
<em>weight of the ball, W = 0.14 N</em>

The impulse experienced by the ball is calculated as follows;

$Ft = \Delta P$

where;

$Ft$ is impulse

$\Delta P$ is change in momentum

The time of motion of the ball is calculated as follows;

$t = \frac{\Delta P}{F} \\\\t = \frac{0.9 - 0}{0.14} \\\\t = 6.43 \ s$

Thus, the time spent in the air by the ball at the given momentum is 6.43 s.

Learn more here:brainly.com/question/13468390

7 0

2 years ago

Sonar signals and infrared light are are used to send messages to submarines deep under water. If we compare the two signals, wh

WARRIOR [948]

What are the statement choices?

6 0

3 years ago

5) In the last part of step 7 of the procedure, you measured the resistance of the flashlight when it had no current passing thr

Andreyy89

Answer:

Following are the responses to this question:

Explanation:

The small current passes thru the capacitor of the strain gauge and the current is generated throughout the resistor. For the very first time, in contrast to what we calculate, its resistance of the multimeter is quite high and therefore the small stream flowing through the bulb would have very little impact on the measure. Thus, as the current flows through the flashbulb, this same calculation is of excellent price, its material is heated and resistance varies with increase. Therefore, when the bulb will be on, sensitivity is greater.

6 0

3 years ago

A 4 kg rock is dropped from 5 m. There is no friction. What kind of energy does is have before? What kind of energy does it have

denpristay [2]

1) The total mechanical energy of the rock is:
$E=U+K$
where U is the gravitational potential energy and K the kinetic energy.

Initially, the kinetic energy is zero (because the rock starts from rest, so its speed is zero), and the total mechanical energy of the rock is just gravitational potential energy. This is equal to
$E_i=U=mgh$
where $m=4 kg$ is the mass, $g=9.81 m/s^2$ is the gravitational acceleration and $h=5 m$ is the height.
Putting the numbers in, we find the potential energy
$U=mgh=(4 kg)(9.81 m/s^2)(5 m)=196.2 J$

2) Just before hitting the ground, the potential energy U is zero (because now h=0), and all the potential energy of the rock converted into kinetic energy, which is equal to:
$E_f=K= \frac{1}{2}mv^2$
where v is the speed of the rock just before hitting the ground. Since the mechanical energy of the rock must be conserved, then the kinetic energy K before hitting the ground must be equal to the initial potential energy U of the rock:
$K=U=196.2 J$

3) For the work-energy theorem, the work W done by the gravitational force on the rock is equal to the variation of kinetic energy of the rock, which is:
$W=196.2 J-0 J=196.2 J$

6 0

3 years ago