Question

PLEASE answer just one please i really need help thank you so much


Gas/Earth's Atmosphere: According to National Geographic, Historically, it’s been difficult to pin that point at a particular altitude. In the 1900s, Hungarian physicist Theodore von Kármán determined the boundary to be around 50 miles up, or roughly 80 kilometers above sea level. Today, though, the Kármán line is set at what National Oceanic and Atmospheric Administration (NOAA) calls “an imaginary boundary” that’s 62 miles up, or roughly a hundred kilometers above sea level. The "height" of the atmosphere to the Von Karman line is about 100 km (62.5 miles). The radius of the Earth is 64000 km. What percentage of Earth's radius is the height of the atmosphere?

2. Solids: Metals expand when heated and contract when cooled according to a coefficient of linear expansion. The coefficient of linear expansion for aluminum is a = 25 x 10^-6 (deg C)^-1, where a = (delta L)/ (L initial x delta T). The coefficient of linear expansion is equal to the change in length divided by the original length and the change in temperature. Determine how much longer is a piece of aluminum siding which measures 3.66 m on a cold winter day of -28 deg C compared to a very hot summer day at 39 deg C.

3. . Liquids: The pressure due to liquid can be determined by Pressure = weight density x depth. The weight density of fresh water is 9800 N/ m^3. Calculate the water pressure (in Pascals-(Pa)) at the base of the Hoover Dam. The depth of the water behind the dam is 220 m. (Neglect the pressure due to the atmosphere).

4.Solids & Elasticity: Within a springs limit of elasticity a spring will stretch according to Hooke's Law where F = k x (X) where k is the spring constant. If a weight of 10 N stretches a certain spring 3 cm, a) Determine the spring constant k. b) Determine how much stretch will occur if you double the weight with a force of 20 N? c) Using g=9.8 m/s^2 determine the mass of the 10 N weight and round your answer to 3 significant digits. *

Coulomb's Law: Coulomb's law is F = k (q1xq2)/ r^2 where k = 9 x 10^9 C^2/m^2. a) Sketch the charges and use Coulomb's law to determine the electric force between two charged particles where q1 = -5 x 10^-3 C and q2 = -1 x 10^-3 C. Q1 and Q2 are separated by a distance of 0.25 m. b) Determine whether the electric force attractive or repulsive and explain your answer?

A particle physicist is studying a particle decay process. The analysis from one experiment shows a particle of charge +3e decaying to form three new particles. One of the new particles has a charge +2e while another is a neutral particle with zero charge. What is the charge of the third particle, Q?

A metal cube with positive charge +Q is brought into contact with an uncharged metal cylinder. Which choice best describes the net movement of charges?

Conservation of Charge Review: Complete the sentence with the correct word(s): a) Charge is neither created nor destroyed, it can only be (siphoned / transferred/ added) from one system to another. b). Conductors are materials that permit (protons/ neutrons/ electrons/ quarks) to move freely through them, such as most metals. c) People (always/ never/ correctly/ mistakenly) think that an object gets positive charge by receiving extra (high-energy/ negative/ positive) charges. d) Protons have positive charge and are bound to the object, while electrons can (oscillate/ be transferred) between objects. e) When an object’s net (force / charge) becomes more positive, it has lost electrons.

Applying Conservation of Charge: A researcher is analyzing a particle decay process. The data for one experiment shows a particle of charge -3e, decaying to form two new particles. One of the new particles has a charge of -e.

How do objects get electrically CHARGED? Due to electrons being rubbed off of one thing onto another results in a POLARIZATION electric charge, which explains why socks cling in the dryer or if you rub a balloon on your hair you can stick it to the wall due to the polarization that you have created by rubbing electrons off your hair onto the balloon. This Physics "Thundercat" has been "supercharged" as evidenced by the styrofoam "packing peanuts" stuck to his fur. State 3 ways charge can be transferred between objects. (Hint: Based on the Khan Academy Video on conductors and insulators

Complete the sentence with the correct word choices: When charge is transferred between objects, it’s only the electrons that move. An electron a) (can or can’t) be broken into smaller pieces, so charge always changes in b) ( multiples or fractions) of the elementary charge. This property of electrons means that charge is quantized and the charge on any object must be c) ( a ratio or an integer multiple) of the elementary charge. *

Answer 1

Answer:

I answered Number 4 (Solids and Elasticity)

Explanation:

Part a)

If a weight of 10 N stretches a certain spring 3 cm, a) Determine the spring constant k.

Solution:

To determine the spring constant we use the formula F = k x (X)  

where ,

F is the force applied in this case 10 N

x is the displacement of the spring’s end from its equilibrium position in this case 3 cm

$F=kx\\10=k(3)\\10/3=k\\k=3.33\ N/cm$

Part b)

b) Determine how much stretch will occur if you double the weight with a force of 20 N?

Solution:

If we double the weight to 20 N we need to find the need to find the new stretch of the spring which is x. But we know the spring constant which is k so it becomes,

$F=kx\\20=3.33x\\20/3.33=x\\x=6.00\ cm$

So we can see that if we double the Force the stretch is also doubled thus showing us a direct variation as seen in the formula F = k x (X)

Part c)

c) Using g=9.8 m/s^2 determine the mass of the 10 N weight and round your answer to 3 significant digits.

Solution:

The formula of weight is,

$W=mg$

where,

w is the weight of the object in Newtons (N) which is 10 in this case

m is the mass of the object in kilograms (kg) we to need to find in this case and,

g is acceleration due to gravity which is constant 9.8 m/s^2

so now,

$W=mg\\10=m(9.8)\\10/9.8=m\\m=1.02\ kg$