1 a neutron star is formed when an object like the sun collapses. Suppose a uniform spherical star of mass M and radius R collapses to a uniform sphere of radius 10^-5 R. If the original star has a rotation rate of 1 rev each 25 days, (like the sun) what will be the rotation rate of the neutron star? WHY?

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1 a neutron star is formed when an object like the sun collapses. Suppose a uniform spherical star of mass M and radius R collapses to a uniform sphere of radius 10^-5 R. If the original star has a rotation rate of 1 rev each 25 days, (like the sun) what will be the rotation rate of the neutron star? WHY? Please give detailed explanation for BOTH questions. ——–
#2 a large horizontal disk is rotating on a vertical axis through its center; for the disk I = 4000 kg m^2. The disk is coasting at a rate of .150 rev/s when a 90 kg person drops onto the disk from an overhanging tree limb. The person lands and remains at a distance of 3 m from the axis of rotation. What will be the rate of rotation after the person has landed

1) A football team is in a position to kick a field goal to win a game. The ball is placed 36 m (approximately 39 yards) from the goalposts. The kicker kicks the ball with a resultant velocity of 20 m/s at an angle of 33°. List your knowns: (2 pts)

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1) A football team is in a position to kick a field goal to win a game. The ball is placed 36 m (approximately 39 yards) from the goalposts. The kicker kicks the ball with a resultant velocity of 20 m/s at an angle of 33°.
List your knowns: (2 pts)
What was the initial horizontal velocity? (2 pts)
What was the initial vertical velocity? (2 pts)
How long was the ball in the air (total flight time)? (4 pts)
What was the horizontal distance traveled? Did they win? (4 pts)
Calculate the following quantities for the diagram shown below: (16 points total)
a. The angular velocity at the hip over each time interval (6 points)
b. The angular velocity at the knee over each time interval (6 points)
Would it be meaningful information to calculate the average angular velocities at the hip and knee for the movement shown? Provide a rationale for your answer. (4 points)
C:UsersaesquivelDocumentsKIN 3580ch11_labeledch11_labeledhaL76442_un1105.jpg
A soccer ball is kicked from the playing field. If the ball is in the air for 2.2 s (total flight time), what is the maximum height achieved? (4 points) (neglect air resistance)
Two cyclists B1 and B2) are racing at exactly the same velocity (say, 12 m/s) and come to a curve in the road (point A). At this point they are tied. Throughout the first half of the curve (points A-C), it appears that the cyclist in the outside lane (B2) remains tied with the cyclist in the inside lane (B1). Assume that the cyclist in the inside lane (B1) maintains a constant velocity. Using terms such as “constant”, “zero”, “same”, “increase”, “decrease”, “positive”, “negative” etc. answer the following questions:
a) What are the differences (if any) between the linear distances traveled by the cyclists between points A and C. List the equation that explains this. (4 points)
B1
B1
B2
B1
B2
B2
b) What are the differences (if any) between the tangential (linear) velocities of the cyclists at points A and C. List the equation that explains this. (4 points)
c) What are the differences (if any) between the tangential (linear) accelerations of the cyclists
between points A and C. List the equation that explains this. (4 points)
d) What is the difference (if any) between the radial acceleration of B1 at points A and C. What is the difference (if any) between the radial acceleration of B2 at points A and C. List the equation that explains this. (4 points)

1) A football team is in a position to kick a field goal to win a game. The ball is placed 36 m (approximately 39 yards) from the goalposts. The kicker kicks the ball with a resultant velocity of 20 m/s at an angle of 33°. List your knowns: (2 pts)

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1) A football team is in a position to kick a field goal to win a game. The ball is placed 36 m (approximately 39 yards) from the goalposts. The kicker kicks the ball with a resultant velocity of 20 m/s at an angle of 33°.
List your knowns: (2 pts)
What was the initial horizontal velocity? (2 pts)
What was the initial vertical velocity? (2 pts)
How long was the ball in the air (total flight time)? (4 pts)
What was the horizontal distance traveled? Did they win? (4 pts)
Calculate the following quantities for the diagram shown below: (16 points total)
a. The angular velocity at the hip over each time interval (6 points)
b. The angular velocity at the knee over each time interval (6 points)
Would it be meaningful information to calculate the average angular velocities at the hip and knee for the movement shown? Provide a rationale for your answer. (4 points)
C:UsersaesquivelDocumentsKIN 3580ch11_labeledch11_labeledhaL76442_un1105.jpg
A soccer ball is kicked from the playing field. If the ball is in the air for 2.2 s (total flight time), what is the maximum height achieved? (4 points) (neglect air resistance)
Two cyclists B1 and B2) are racing at exactly the same velocity (say, 12 m/s) and come to a curve in the road (point A). At this point they are tied. Throughout the first half of the curve (points A-C), it appears that the cyclist in the outside lane (B2) remains tied with the cyclist in the inside lane (B1). Assume that the cyclist in the inside lane (B1) maintains a constant velocity. Using terms such as “constant”, “zero”, “same”, “increase”, “decrease”, “positive”, “negative” etc. answer the following questions:
a) What are the differences (if any) between the linear distances traveled by the cyclists between points A and C. List the equation that explains this. (4 points)
B1
B1
B2
B1
B2
B2
b) What are the differences (if any) between the tangential (linear) velocities of the cyclists at points A and C. List the equation that explains this. (4 points)
c) What are the differences (if any) between the tangential (linear) accelerations of the cyclists
between points A and C. List the equation that explains this. (4 points)
d) What is the difference (if any) between the radial acceleration of B1 at points A and C. What is the difference (if any) between the radial acceleration of B2 at points A and C. List the equation that explains this. (4 points)

1. A 1 kg block of wood is moving with a velocity of 10 m s -1 on top of a table. The coefficient of kinetic friction between the block of wood and the table is 0.1. The block of wood is a cube with sides of 12 cm. a) How far does the block move before coming to a stop?

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1. A 1 kg block of wood is moving with a velocity of 10 m s -1 on top of a table. The coefficient of kinetic friction between the block of wood and the table is 0.1. The block of wood is a cube with sides of 12 cm.
a) How far does the block move before coming to a stop? b) If momentum id conserved, where did the momentum of the block go? c) The block slows down because of the frictional force between the block and the block. However, if the frictional force acts at the bottom of the block and the blocks center of mass is in the center of the block then there must be a torque acting on the block. Calculate this torque. Why doesn’t this torque cause the block to rotate?
2. In 2286, Admiral Kirk and his crew were forced to use the sling shot effect in a stolen Klingon Bird-of-Prey to travel back in time to the late 20th century to retrieve two humpback whales. The stolen Klingon Bird-of-Prey traveled towards the sun at a velocity of v, while the sun was moving towards them at a velocity of u, then traveled around the sun (using the sun’s gravitational field) such that the stolen Klingon Bird-of-Prey was now moving in the opposite direction from whence it started, with a new velocity, vnew. Find vnew in terms of u and v, assuming the mass of the sun is much larger than the mass of the spaceship.
3. Consider holding a carton of milk in your hand, as shown in the image. The force of the bicep muscle acts at an angle of 15o to the vertical, while the weight of the arm and the milk both act downwards. The distance from the elbow to where the bicep muscle is attached via the the distal bicep tendons to the radius and ulna bones is 5 cm. The distance from the elbow to the center of mass of the forearm is 16.5 cm and the distance from the elbow to the hand, holding the milk, is 35 cm. The forearm has a mass of 4 kg and the milk carton a mass of 2 kg.
a) Assuming the forearm is kept perfectly horizontal, find the tension in the bicep muscle. b) As a function of the angle of the forearm with respect to the horizontal direction (as the forearm is lowered) calculate the tension in the bicep muscle. c) Include a plot of tension in the bicep as a function of the angle of the forearm relative to the horizontal (don’t forget to label axis).

A skateboarder in a death-defying stunt decides to launch herself from a ramp on a hill. The skateboarder leaves the ramp at a height of 1.4 m above the slope, traveling 15 m s-1 and at an angle of 40o to the horizontal. The slope is inclined at 45o to the horizontal. a) How far down the slope does the skateboarder land? b) How long is the skateboarder in the air? c) With what velocity does the skateboarder land on the slope?

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. A skateboarder in a death-defying stunt decides to launch herself from a ramp on a hill. The skateboarder leaves the ramp at a height of 1.4 m above the slope, traveling 15 m s-1 and at an angle of 40o to the horizontal. The slope is inclined at 45o to the horizontal.
a) How far down the slope does the skateboarder land? b) How long is the skateboarder in the air? c) With what velocity does the skateboarder land on the slope?
A car is driving around a bank curve such that it can safely go around a circular curve at a given velocity, vo, even when on ice (zero friction). Any slower and the car would slide down towards the center of the circle, any faster and the car would slide up the hill and away from the center of the circle. If a static frictional coefficient, , is introduced then the car can safely navigate around the curve at any speed between a minimum speed of vmin and a maximum speed of vmax. Can you find expressions for vmin and vmax as a function of vo, and the radius of the road, R.
In a cardiac stress test the patient is required to walk on an inclined treadmill. Imagine that the patients mass is 80 kg and that the inclined treadmill is at a slope of 15o. The efficiency of the human body can be taken to be 25%.
a) Obtain an expression for the power required by the patient to maintain a velocity of 3 m s-1. b) How long would the patient have to walk on the treadmill to burn the energy contained in a bottle of beer, a slice of pizza and a jelly doughnut?

A skateboarder in a death-defying stunt decides to launch herself from a ramp on a hill. The skateboarder leaves the ramp at a height of 1.4 m above the slope, traveling 15 m s-1 and at an angle of 40o to the horizontal. The slope is inclined at 45o to the horizontal. a) How far down the slope does the skateboarder land? b) How long is the skateboarder in the air? c) With what velocity does the skateboarder land on the slope?

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. A skateboarder in a death-defying stunt decides to launch herself from a ramp on a hill. The skateboarder leaves the ramp at a height of 1.4 m above the slope, traveling 15 m s-1 and at an angle of 40o to the horizontal. The slope is inclined at 45o to the horizontal.
a) How far down the slope does the skateboarder land? b) How long is the skateboarder in the air? c) With what velocity does the skateboarder land on the slope?
A car is driving around a bank curve such that it can safely go around a circular curve at a given velocity, vo, even when on ice (zero friction). Any slower and the car would slide down towards the center of the circle, any faster and the car would slide up the hill and away from the center of the circle. If a static frictional coefficient, , is introduced then the car can safely navigate around the curve at any speed between a minimum speed of vmin and a maximum speed of vmax. Can you find expressions for vmin and vmax as a function of vo, and the radius of the road, R.
In a cardiac stress test the patient is required to walk on an inclined treadmill. Imagine that the patients mass is 80 kg and that the inclined treadmill is at a slope of 15o. The efficiency of the human body can be taken to be 25%.
a) Obtain an expression for the power required by the patient to maintain a velocity of 3 m s-1. b) How long would the patient have to walk on the treadmill to burn the energy contained in a bottle of beer, a slice of pizza and a jelly doughnut?