Desert sand is very hot in the day and very cool at night. What does this indicate about its specific heat capacity?

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Desert sand is very hot in the day and very cool at night. What does this indicate about its specific heat capacity?
Essay answers are limited to about 500 words (3800 characters maximum, including spaces).
16.40
On a cold day, why does a metal doorknob feel colder than the wooden door?
Essay answers are limited to about 500 words (3800 characters maximum, including spaces).
16.87
Your friend states that the average speed of all hydrogen and nitrogen molecules in a gas is the same. Do you agree or disagree, and why?
Essay answers are limited to about 500 words (3800 characters maximum, including spaces).
17.57
Why are icebergs often surrounded by fog?
Essay answers are limited to about 500 words (3800 characters maximum, including spaces).
17.75
When you boil potatoes, will your cooking time be reduced with vigorously boiling water instead of gently boiling water? (Directions for cooking spaghetti call for vigorously boiling water – not to lessen cooking time but to prevent something else. If you don’t know what it is, ask a cook.)
Essay answers are limited to about 500 words (3800 characters maximum, including spaces).
18.61
Could you cool a kitchen by leaving the refrigerator door open and closing the kitchen door and windows? Explain.
Essay answers are limited to about 500 words (3800 characters maximum, including spaces)

A stone falls from rest from the top of a cliff. A second stone is thrown downward from the same height 3.4 s later with an initial speed of 66.64 m/s. They hit the ground at the same time. How long does it take the first stone to hit the ground?

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A stone falls from rest from the top of a cliff. A second stone is thrown downward from the same height 3.4 s later with an initial speed of 66.64 m/s. They hit the ground at the same time. How long does it take the first stone to hit the ground? The acceleration of gravity is 9.8 m/s2 . Answer in units of s
In your frame, a certain galaxy is moving at a high speed in the x-direction. Relative to the galaxy, a certain comet in the galaxy is also moving at a high speed in the x-direction. Let a be the galaxy’s speed with respect to you, b be the comet’s speed with respect to the galaxy, and c be the comet’s speed with respect to you. Then
Select one:
a. a + b > c
b. a + b < c c. a + b = c d. a 2 + b 2 = c 2 Jamal is skating on a sidewalk. His initial velocity is 0.0 m/s ; 35 seconds later hid velocity is 5.0 m/s. What is his acceleration

Convert Kelvin temperature 2000 K to Cel- sius. Answer in units of ◦C.

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Convert Kelvin temperature 2000 K to Cel- sius. Answer in units of ◦C.
Question 2, chap 119, sect 5.
part 1 of 2 10 points
At 32◦C, an aluminum ring has an inner di- ameter of 6 cm and a brass rod has a diameter of 6.01 cm. If the temperature coefficient of expansion
for brass is αb = 1.9× 10 −5 (◦C)−1 and the
temperature coefficient of expansion for alu- minum is αa = 2.4× 10
−5 (◦C)−1, to what temperature must the ring be heated so that it will just slip over the rod? Answer in units of ◦C.
Question 3, chap 119, sect 5.
part 2 of 2 10 points
To what temperature must both be heated so that the ring just slips over the rod? Answer in units of ◦C.
Question 4, chap 119, sect 5.
part 1 of 1 10 points
A 27 gallon steel container is completely filled with carbon tetrachloride. Its temper- ature is 7 ◦C. The average volume coeffi- cient of expansion for carbon tetrachloride is 0.000581(◦C)−1. How much carbon tetrachloride will spill
over when the temperature rises to 26◦C? As- sume that the steel container is held at con- stant temperature so that its volume remains constant. Answer in units of gal.
Question 5, chap 119, sect 5.
part 1 of 1 10 points
A square hole 10.5 cm along each side is cut in a sheet of copper. Calculate the change in the area of this hole
if the temperature of the sheet is increased by 26 K. The coefficient of linear expansion of copper is 1.7× 10−5 (◦C)−1. Answer in units of cm2.
Question 6, chap 119, sect 5.
part 1 of 2 10 points
A pendulum clock with a brass suspension system is calibrated so that its period is 1 s at 8◦C. If the temperature increases to 44 ◦C, by
how much does the period change? Answer in units of s.
Question 7, chap 119, sect 5.
part 2 of 2 10 points
How much time does the clock gain or lose in one week? Answer in units of s.
Question 8, chap 119, sect 5.
part 1 of 1 10 points
A car has a 31 L steel gas tank filled to the top with gasoline when the temperature is 8◦C. Assume the linear expansion coefficient for steel is 1.1× 10−5 K−1 and the volume expansion of gasoline is 0.0009 K−1. Taking the expansion of the steel tank into
account, how much gasoline spills out of the tank when the car is parked in the sun and its temperature rises to 45◦C? Answer in units of L.
Question 9, chap 119, sect 7.
part 1 of 2 10 points
An air bubble originating from an under- water diver has a radius of 6 mm at some depth h. When the bubble reaches the surface of the water, it has a radius of 7.1 mm. The acceleration of gravity is 9.8 m/s2 . Assuming the temperature of the air in the
bubble remains constant, determine the depth of the diver. Answer in units of m.
Question 10, chap 119, sect 7.
homework 12 – ALGHAMDI, ALI – Due: Nov 18 2017, 11:00 pm (Central time) 2
part 2 of 2 10 points
Determine the absolute pressure at this depth. Answer in units of kPa.
Question 11, chap 119, sect 7.
part 1 of 1 10 points
A cylinder with a movable piston contains gas at a temperature of 34.9◦C, a volume of 2 m3, and an absolute pressure of 20400 Pa. What will be its final temperature if the
gas is compressed to 0.57 m3 and the absolute pressure increases to 86837 Pa? Answer in units of ◦C.
Question 12, chap 119, sect 7.
part 1 of 1 10 points
An auditorium is 9 m high, 41 m long, and 20 m wide. How many molecules of air are needed to
fill the auditorium at 32◦C and 99.9 kPa pres- sure? The gas constant is 8.31 J/K ·mol.
Question 13, chap 120, sect 2.
part 1 of 1 10 points
A 2 kg block of ice at a temperature of 0.0◦C and an initial speed of 6.9 m/s slides across a level floor. If 330000 J are required to melt 1 kg of
ice, how much ice melts, assuming that the initial kinetic energy of the ice block is entirely converted to the ice’s internal energy? Answer in units of kg.
Question 14, chap 120, sect 3.
part 1 of 1 10 points
A 755 kg car moving at 24 m/s brakes to a stop. The brakes contain about 14 kg of iron that absorb the energy. What is increase in temperature of the
brakes? Assume the specific heat of iron is 450 J/kg ·◦ C. Answer in units of ◦C.
Question 15, chap 120, sect 5.
part 1 of 1 10 points
A 4.9 g lead bullet moving at 278 m/s strikes a steel plate and stops. If all its kinetic energy is converted to ther-
mal energy and none leaves the bullet, what is its temperature change? Assume the specific heat of lead is 128 J/kg/◦C. Answer in units of ◦C.
Question 16, chap 120, sect 6.
part 1 of 1 10 points
A 0.013 g cube of ice at 0◦C is added to 0.442 g of soup at 81.1◦C. The specific heat of water is 4186 J/kg ·◦C
and the latent heat of fusion for water is 333000 J/kg. Assuming that the soup has the same spe-
cific heat capacity as water, find the final tem- perature of the soup after the ice has melted. Answer in units of ◦C.
Question 17, chap 120, sect 6.
part 1 of 1 10 points
At a foundry, 24 kg of molten aluminum with a temperature of 660.4◦C is poured into a mold. The specific heat of aluminum is
899 J/kg ·◦C and its latent heat of fusion is 397000 J/kg. If this is carried out in a room containing
140 kg of air at 25◦C, what is the temperature of the air after the aluminum is completely solidified? Assume that the specific heat ca- pacity of air is 1000 J/kg ·◦C and that the melting point of aluminum is 660.4◦C. Answer in units of ◦C.

You are required to develop two sport business case studies that focus on different aspects of the business of running sport and from various perspectives. They could be participant or fan orientated, goods or service based.

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You are required to develop two sport business case studies that focus on different aspects of the business of running sport and from various perspectives. They could be participant or fan orientated, goods or service based.
Task
Select your two contrasting sport based businesses and undertake the following (1000 words per case study):
1.  Describe the nature of the sport business, it’s structure and activities (500 words)
2.  Critically analyse and then summarise, the issues and challenges the organisation faces in the current business and sporting environment (500 words)

World-class sprinters can accelerate out of the starting blocks with an acceleration that is nearly horizontal and has magnitude 15m/s2. 1) How much horizontal force F must a sprinter of mass 51kg exert on the starting blocks to produce this acceleration?

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World-class sprinters can accelerate out of the starting blocks with an acceleration that is nearly horizontal and has magnitude 15m/s2.
1) How much horizontal force
F must a sprinter of mass 51kg exert on the starting blocks to produce this acceleration?
2) Which body exerts the force that propels the sprinter, the blocks or the sprinter?
A particle is moving along a straight line with the acceleration a (12t-3t^1/2)ft/s^2 where t is in seconds. Determine the velocity of the particle as a function of time. When t=0,v=0 , and s= 15 .
A tennis ball is given horizontal velocity of 8 m/s when it is hit at a height of 1.8 m above the ground. It is in air for how many seconds?

1. An object weighs 3000 N. What is the object's mass? _______kg

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1.
An object weighs 3000 N. What is the object’s mass?
_______kg
2.
An object weighs 2700 lb. What is the object’s weight in N?
_______N
3.
An object weighs 3500 N. What is the object’s weight in lb?
_______lb
4.
The mass of a certain elephant is 2,667 kg.
(a) Find the elephant’s weight in newtons.
_______N
(b) Find its weight in pounds.
_______lb
5.
A jet aircraft with a mass of 4,275 kg has an engine that exerts a force (thrust) equal to 59,400 N.
(a) What is the jet’s acceleration? (Give the magnitude.)
________
(b)What is the jet’s speed after it accelerates for 9 s? (Assume it starts from rest.)
________
(c) How far does the jet travel during the 9 s?
________


6.
A motorcycle and rider have a total mass equal to 335 kg. The rider applies the brakes, causing the motorcycle to accelerate at a rate of
−4 m/s2.
What is the net force on the motorcycle? (Indicate the direction with the sign of your answer.)
________
7.
In an experiment performed in a space station, a force of 62 N causes an object to have an acceleration equal to 2 m/s2. What is the object’s mass?
________
8.
On aircraft carriers, catapults are used to accelerate jet aircraft to flight speeds in a short distance. One such catapult takes a 17,800-kg jet from 0 to 67 m/s in 2.7 s. (Assume the catapult acts in the positive horizontal direction. Indicate the direction with the sign of your answer where appropriate.)
(a) What is the acceleration of the jet in m/s2?
________
(b) What is the acceleration of the jet in g’s?
________
(c) How far does the jet travel while it is accelerating?
________
(d) How large is the force that the catapult must exert on the jet?
__________
9.
An airplane is built to withstand a maximum acceleration of 7 g. If its mass is 1,210 kg, what size force would cause this acceleration?
_________
10.
Under certain conditions, the human body can safely withstand an acceleration of 10 g.
(a) What net force would have to act on someone with mass of 75 kg to cause this acceleration?
_________
(b) First, find the weight of such a person in pounds. Second convert the answer obtained in part (a) into pounds.
Weight of person _________
Net force from
part(a) _________


11.
A race car rounds a curve at 55 m/s. The radius of the curve is 434 m, and the car’s mass is 685 kg. (Assume the car’s speed remains constant. Take the radially inward direction to be positive. Indicate the direction with the sign of your answer.)
(a) What is the car’s (centripetal) acceleration?
_________
(b) What is it in g’s?
_________
(c) What is the centripetal force acting on the car?
_________


12.
A hang glider and its pilot have a total mass equal to 128 kg. While executing a 360° turn, the glider moves in a circle with a 9 m radius. The glider’s speed is 13 m/s. (Assume the glider turns along the horizontal plane.)
(a) What is the net force on the hang glider?
__________
(b) What is the acceleration?
____________
13.
As a spacecraft approaches a planet, the rocket engines on it are fired (turned on) to slow it down so it will go into orbit around the planet. The spacecraft’s mass is 1,925 kg and the thrust (force) of the rocket engines is 345 N. If its speed must be decreased by 1,134 m/s, how long (in minutes) must the engines be fired? (Ignore the change in the mass as the fuel is burned.)
___________
14.
As a baseball is being caught, its speed goes from 27 to 0 m/s in about 0.008 s. Its mass is 0.145 kg. (Take the direction the baseball is thrown to be positive.)
(a) What is the baseball’s acceleration in m/s2? (Indicate the direction with the sign of your answer.)
_________
What is the baseball’s acceleration in g’s? (Indicate the direction with the sign of your answer.)
_________
(b) What is the size of the force acting on it?
___________
15.
As a rocket ascends, its acceleration increases even though the net force on it stays constant. Why? (Assume a traveling distance small enough that the thrust, acceleration due to gravity and atmosphere do not change.)
__The faster a rocket moves the more acceleration is imparted to it from a given force.
__The rocket’s mass decreases as its fuel is consumed. The same net force acting on a smaller mass results in a larger acceleration.
__As the rocket ascends, fuel is burned at a faster rate resulting in a larger acceleration.
__As a rocket ascends it’s momentum increases with it’s speed. The greater the momentum of the rocket, the greater the acceleration imparted to it from a given force.
16.
A person is riding on a train while watching the display on a GPS unit. The person notices that both the “speed” and the “heading” readings are not changing. What can the person conclude about the net force acting on the train car?
____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
17.
A car starts at positionx = 0, with an initial velocity of 4.7 m/s and an acceleration of 0 m/s2. What is its position when the elapsed time is 6.5 s? (Please be sure to include units in your answer. Express your answer to one decimal point.)
________
18.
A car has an initial position of x = 0 m, an initial velocity of 0 m/s, and a constant acceleration of 2.6 m/s2. What is its position when the time is 4.2 seconds? (Please be sure to include units in your answer. Express your answer to one decimal point.)
________
19.
A car has an initial position of x = 0 m, an initial velocity of 0 m/s, and a constant acceleration of 4.1 m/s2. What is its velocity when the time is 5.7 seconds? (Please be sure to include units in your answer. Express your answer to one decimal point.)
________