Which of e following conditions would decrease the ability of a person to bear a sound?

An 8 g bullet leaves the muzzle of a rifle with

Elena-2011 [213]

Answer: 1872 N

Explanation:

This problem can be solved by using one of the Kinematics equations and Newton's second law of motion:

$V^{2}=V_{o}^{2} + 2ad$ (1)

$F=ma$ (2)

Where:

$V=611.9 m/s$ is the bullet's final speed (when it leaves the muzzle)

$V_{o}=0$ is the bullet's initial speed (at rest)

$a$ is the bullet's acceleration

$d=0.8 m$ is the distance traveled by the bullet before leaving the muzzle

$F$ is the force

$m=8 g \frac{1 kg}{1000 g}=0.008 kg$ is the mass of the bullet

Knowing this, let's begin by isolating $a$ from (1):

$a=\frac{V^{2}}{2d}$ (3)

$a=\frac{(611.9 m/s)^{2}}{2(0.8 m)}$ (4)

$a=234013.5063 m/s^{2} \approx 2.34(10)^{5} m/s^{2}$ (5)

Substituting (5) in (2):

$F=(0.008 kg)(2.34(10)^{5} m/s^{2})$ (6)

Finally:

$F=1872 N$

4 0

3 years ago

To aid in the prevention of tooth decay, it is recommended that drinking water contain 0.800 ppm fluoride, F−. How many grams of

Leviafan [203]

Answer:

2.23 × 10^6 g of F- must be added to the cylindrical reservoir in order to obtain a drinking water with a concentration of 0.8ppm of F-

Explanation:

Here are the steps of how to arrive at the answer:

The volume of a cylinder = ((pi)D²/4) × H

Where D = diameter of the cylindrical reservoir = 2.02 × 10^2m

H = Height of the reservoir = 87.32m

Therefore volume of cylindrical reservoir = (3.142×202²/4)m² × 87.32m = 2798740.647m³

1ppm = 1g/m³

0.8ppm = 0.8 × 1g/m³

= 0.8g/m³

Therefore to obtain drinking water of concentration 0.8g/m³ in a reservoir of volume 2798740.647m³, F- of mass = 0.8g/m³ × 2798740.647m³ = 2.23 × 10^6 g must be added to the tank.

Thank you for reading.

4 0

3 years ago

Reginald slipped and broke his leg in his kitchen when he ran inside to grab a cookie. His mother had just mopped the floor. Wha

padilas [110]

Answer:

A. <u>The water decreases the friction between the floor and the feet </u>

Explanation: Think about it like this, when your in the shower and water is on your skin, you can scrub it fluidly, but when the water dries in your towel, there is more friction when your rub your skin, this is because the molecules in water aren't as compact as solids, so anything acting against it, is most likely to disperse from it.

3 0

3 years ago

A hockey puck sliding along frictionless ice with speed v to the right collides with a horizontal spring and compresses it by 1.

patriot [66]

Answer:

The spring's maximum compression will be 2.0 cm

Explanation:

There are two energies in this problem, kinetic energy $K= \frac{mv^{2}}{2}$ and elastic potential energy $U= \frac{kx^{2}}{2}$ (with m the mass, v the velocity, x the compression and k the spring constant. ) so the total mechanical energy at every moment is the sum of the two energies:

$E=K+U$

Here we have a situation where the total mechanical energy of the system is conserved because there are no dissipative forces (there's no friction), so:

$E_{i}=E_{f}$

$K_{i}+U_{i}=K_{f}+U_{f}$

Note that at the initial moment where the hockey puck has not compressed the spring all the energy of the system is kinetic energy, but for a momentary stop all the energy of the system is potential elastic energy, so we have:

$K_{i} = U_{f}$

$\frac{mv^{2}}{2}=\frac{kx^{2}}{2}$ (1)

Due conservation of energy the equality (1) has to be maintained, so if we let k and m constant x has to increase the same as v to maintain the equality. Therefore, if we increase velocity to 2v we have to increase compression to 2x to conserve the equality. This is 2(1.0) = 2.0 cm

7 0

3 years ago

Help me write this three paragraph Physics essay. I'll Venmo you, give me asking price.

viktelen [127]

Answer:

Physics, or the study of matter, energy, and the interactions between them, helps us to understand the laws and rules that govern the physical world. Not every student will grow up and study physics on a deeper level, but everyone uses basic physics concepts to navigate everyday life.A

Physics is a natural science that involves the study of matter and its motion through space and time, along with related concepts such as energy and force. More broadly, it is the study of nature in an attempt to understand how the universe behaves.Physics helps you to understand the world around you, and satisfy your curiosity. Studying physics develops your critical thinking and problem-solving skills. Physicists are versatile, which opens a wide range of future careers.

8 0

3 years ago