A brass ring of diameter 10.00 cm at 16.4°C is heated and slipped over an aluminum rod of diameter 10.01 cm at 16.4°C. Assume the average coefficients of linear expansion are constant.

(a) To what temperature must the combination be cooled to separate the two metals?

? °C

(b) What if the aluminum rod were 11.76 cm in diameter?

? °C

what causes fictitious force in a non-rotating reference frame?

7. What is the primary mechanism for maintaining homeostasis?

Select one:

a. positive feedback

b. negative feedback

c. intrinsic control

d. extrinsic control

e. homeostatic control

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The correct answer is: negative feedback plz explain a.b c d e all explain in short answer

Why does tension not appear in the universal wave equation?

How the world has reacted to global climate change aka greenhouse gasses rising. describe with evidence?

N12R.3Imagine you are the orbital engineer for the first NASA space shot to Ceres, the largest known asteroid. Ceres’s nearly circular orbit around the sun has a radius of R = 2.77 AU. After being launched from the earth, the probe will initially be in a circular orbit around the sun with the same radius (rc = 1.0 AU) and the same orbital speed Inline_Formula as the earth’s orbit. The probe’s rocket engines will then fire briefly to increase the probe’s speed to that speed Inline_Formula needed to put the probe into an elliptical orbit whose initial (and minimum) distance from the sun is rc = 1.0 AU and whose final (and largest) distance from the sun is R = 2.77 AU (this is a Hohmann transfer orbit). (a) How long will it take the probe to get from the earth to Ceres in such an orbit? (b) What is the speed Inline_Formulathat the probe has to have just after firing its engines to be inserted into this orbit? (Assume the duration of the boost is short enough that its distance from the sun is still nearly rc just after the engines have been fired.)

A heavy rainstorm dumps 1.0 cm of rain on a city 7 km wide and 8 km long in a 2-h period.

part a) How many metric tons (1 metricton = 10³ kg) of water fell on the city? (1 cm3 of water has a mass of 1 gram = 10^-3 kg.)

Express your answer using one significant figure.

part b) How many gallons of water fell on the city? (1 gal = 3.785 L.)

Express your answer using one significant figure.

A basketball player is 6ft tall, the player was fouled and gets a free shot from the foul line. The player is 15ft away from the basketball net, and the basket is 10ft off the ground.

a)If the basketball player shoots the ball at an angle of 45 degrees, find the magnitude of the velocity needed to get the ball into the basket

b) If a basketball has a mass of 1kg estimate the force as a vector needed to make the basket

c) Why would the player want to shoot more slowly?

 A chain of many simple sugars is a:

Select one:

a. monosaccharide.

b. polysaccharide.

c. disaccharide.

d. nucleic acid. 

e. fatty acid.

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The correct answer is: polysaccharide.

Question 2

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2. What is/are the major role(s) of the phospholipid bilayer?

Select one:

a. is the source of ATP synthesis.

b. the formation of a barrier that is selectively permeable to lipid-soluble molecules only.

c. is the site of transcription and translation.

d. contains the genetic information required for cellular processes.

e. the formation of a barrier that is selectively permeable to lipid-soluble molecules and to provide a framework for membrane proteins. 

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The correct answer is: the formation of a barrier that is selectively permeable to lipid-soluble molecules and to provide a framework for membrane proteins. 

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3. If a 25% sucrose solution is separated from a 15% sucrose solution by a membrane impermeable to sucrose, but permeable to water, in which direction will net movement of water occur?

Select one:

a. From the 15% sucrose solution to the 25% sucrose solution only.

b. From the 25% sucrose solution to the 15% sucrose solution only.

c. There will be no net movement of water in this case.

d. From the 15% sucrose solution to the 25% sucrose solution and from the 25% sucrose solution to the 15% sucrose solution.

e. None of the answers are correct.

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The correct answer is: From the 15% sucrose solution to the 25% sucrose solution only.

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4. A neuron is exposed to a drug that causes the blockage of Na⁺ leak channels. How will this drug affect the resting membrane potential of the neuron? 
W. The resting membrane potential in this neuron would initially become more positive.
X. The resting membrane potential in this neuron would become around +60 mV.
Y. The resting membrane potential would return to normal following activity of the sodium-potassium pump.
Z. The resting membrane potential in this neuron would become more negative.

Select one:

a. if only W, X and Y are correct

b. if only W and Y are correct

c. if only X and Z are correct

d. if only Z is correct

e. if all are correct

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The correct answer is: if only Z is correct

Question 5

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5. Graded potentials may:
W. initiate an action potential.
X. depolarize the membrane to the threshold voltage.
Y. hyperpolarize the membrane.
Z. be called EPSPs or IPSPs.

Select one:

a.
 if only W, X and Y are correct

b. if only W and Y are correct

c. if only X and Z are correct

d. if only Z is correct

e. if all are correct

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The correct answer is: if all are correct

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6. A higher than normal secretion of the thyroid hormones thyroxine (T4) and tri-iodothyronine (T3) would cause increases in:
W. basal metabolic rate.
X. thyrotropin releasing hormone (TRH).
Y. basal rate of heat production.
Z. thyroid stimulating hormone (TSH).

Select one:

a. if only W, X and Y are correct

b. if only W and Y are correct

c. if only X and Z are correct

d. if only Z is correct

e. if all are correct

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The correct answer is: if only W and Y are correct

Question 7

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7. What is the primary mechanism for maintaining homeostasis?

Select one:

a. positive feedback

b. negative feedback

c. intrinsic control

d. extrinsic control

e. homeostatic control

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The correct answer is: negative feedback

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8. Based on a 28-day cycle, which of the following occurs during days 6-14 of the menstrual cycle? 

Select one:

a. ovulation

b. menstruation

c. proliferative phase

d. secretory phase

e. luteal phase

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The correct answer is: proliferative phase will you help mi to explain all opetion ex w.x .y z from all question in short answer explanations

A 1 3 -kg mass is attached to a spring with stiffness 4 N/m. The damping constant for the system is 2 N-sec/m. The mass is displaced 1 2m to the left and given an initial velocity of 2 m/s to the right.

(a) Determine the equation of the motion of mass and express it in the form A e αt sin(βt + φ) by finding the constants A, α, β and φ in radians.

(b) Find the time t when the mass crosses the equilibrium position for the first time.

(c) Find the maximum displacement of the mass to the right.

A ball is thrown at an angle of θ₀ = 60° above the horizontal with an initial speed of v₀ = 11.5 m/s. What will be the direction of the ball's velocity after 0.62 sec? Submit the angle between the velocity and the horizontal (in degrees).

The angle, θ = _____ deg.

At what time will the velocity of the ball make an angle 12° relative to the horizontal?

The time, t = _____  

Assuming all other factors remain the same, if pulse repetition frequency increases discuss what will happen to the spatial pulse length

As frequency increases comment on what happens to back scatter

EXPERIMENT LINEAR AIR TRACK

1)In the experiment to investigate Newton's second law of motion by using linear air track,explain the function of each apparatus used,which are air track rail,blower,pressure tubr,gliders,flag,photogate,string and pulley.

2)Why do we need to measure the length of the flag to get the accelerationnand why do we use the formula a=2X/t2?.

3)Is there any friction force involves and suggest the ways to improve this experiment

A particle moves in the xy plane with constant acceleration. At t = 0 the particle is at r₁ = (4.0 m) + (3.0 m), with velocity ₁. At t = 3 s, the particle has moved to r₂ = (9 m) − (2.0 m) and its velocity has changed to v₂ = (5.0 m/s) − (6.0 m/s).

i. Find 1 = m/s

ii. What is the acceleration of the particle?

iii. What is the velocity of the particle as a function of time?

iv. What is the position vector of the particle as a function of time?

Consider E as function of the volume and temperature. Write down and expression for dE(V,T). Identify the partial derivatives in terms of known / measurable quantities if possible.