Questions
The trajectory of a rock ejected from the Kilauea volcano, with a velocity of magnitude 46.9...

The trajectory of a rock ejected from the Kilauea volcano, with a velocity of magnitude 46.9 m/s and at angle 35.1 degrees above the horizontal. The rock strikes the side of the volcano at an altitude of 39.1m lower than its starting point. Calculate the magnitude of the rock’s velocity at impact? Use g = 9.8 m/s2.

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A girl of mass, m = 40 kg has osteoporosis which weakens her bones. From a...

A girl of mass, m = 40 kg has osteoporosis which weakens her bones. From a kneeling position, she topples forward onto her elbows with her upper arms extended vertically downwards on impact with the ground. In falling forward, her centre of mass lowers by a height, h = 50 cm and she absorbs all of her kinetic energy from her fall into her two humerus bones (one bone in each upper arm).

Determine an equation for the stress in each humerus bone, ?, in terms of m, h, the acceleration due to gravity, g, Young’s modulus for bone, Y, the cross sectional area of each humerus bone, A and the length of each humerus bone, l. State any laws used. Now, determine the minimum rupture strength required for the girl’s humerus bones such that she doesn’t break them, given in units of N/m2 . Take l = 20 cm, A = 3.0 cm2 and Y = 1.4 x10^10 N/m2 .

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What is limiting the more widespread use of hydrogen as a transportation fuel? Hydrogen fuel is...

What is limiting the more widespread use of hydrogen as a transportation fuel?

Hydrogen fuel is only suitable for compact vehicles

A new infrastructure would be needed for fuel production and distribution

The technology for reducing the emissions of hydrogen-fueled vehicles is expensive

Fears of the public that cars would become hydrogen bombs

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Photons with a wavelength of 599 nm in air enter a plate of flint glass with...

Photons with a wavelength of 599 nm in air enter a plate of flint glass with index of refraction n = 1.66. Find the speed, wavelength, and energy of a photon in the glass. (a) speed (in m/s) m/s (b) wavelength (in m) m (c) energy (in J)

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A hot air balloon has a total mass of 750 kg (not including the air in...

A hot air balloon has a total mass of 750 kg (not including the air in the balloon) and holds a volume of 2.8 x 10^6 L of air. Assume the density of the air outside the balloon to be 1.2 kg/m^3 at a temperature of 20 degrees C and the air pressure is 101.3 kPa inside and outside the balloon. What is the minimum temperature for the air in the balloon to allow for the balloon to float? You can assume the air in the balloon to be an ideal gas and you must consider the mass of the air in the balloon as part of the total mass. Also, assume the molar mass of air to be 29 g/mol. (The answer is 379 K. Please show work.)

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In a rectangular coordinate system, a positive point charge 5.0nC is placed at x=2cm, y=0cm and...

In a rectangular coordinate system, a positive point charge 5.0nC is placed at x=2cm, y=0cm and a negative point charge -5.0nC is placed at x=-2cm,y=0cm. Point P is at x=2cm, y=3cm

K=8.99 x 10^9 (Nxm^2)/C^2

a) Calculate the magnitude of the force between the positive charge and negative charge

b) Draw the electric field vector at point P, caused by the positive charge. Find its magnitude

c) Draw the electric field vector at point P, caused by the negative charge. Find its magnitude

d) Determine the magnitude and direction of the net electric field vector at point P

e) If a charge q=-4.0nC with a mass 2.0 x 10^-6 kg is released from rest at point P, what is its acceleration?

f) Calculate the electric potential at point P

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For an angled launch how would your analysis of the ball's motion have to change if...

For an angled launch how would your analysis of the ball's motion have to change if it fell to a height below it was launched. Clearly identify where and how the analysis changes. Formula used before was Range=Vicos(2(Visin)/g)

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For this problem, assume salt water and fresh water have the same density. A large iceberg...

For this problem, assume salt water and fresh water have the same density.

A large iceberg floats in the ocean. If the iceberg melts, the sea level will:

a) stay the same

b) fall

c) rise <---wrong answer!

Please also provide an explanation!

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Explain why centrifugal force is a false (pseudo) force.

Explain why centrifugal force is a false (pseudo) force.

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A skier traveling 14.0 m/s reaches the foot of a steady upward 20.0o incline and glides...

A skier traveling 14.0 m/s reaches the foot of a steady upward 20.0o incline and glides 11.5 m up along this slope before coming to rest. Using mechanical energy methods what is the coefficient of friction?

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Elmer Fudd pulls a 65.0 kg wooden crate of mass m across the floor with a...

  1. Elmer Fudd pulls a 65.0 kg wooden crate of mass m across the floor with a force F at an angle of 34.0°. The coefficient of friction between the surfaces is m = 0.235. If the crate moves at a constant speed, what is the magnitude of the applied force F?

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A beaker, filled to the very topwith water, weighs 15 N. A 300 g weight is...

A beaker, filled to the very topwith water, weighs 15 N. A 300 g weight is carefully dropped intothe beaker. The water that overflows is wiped away and the beakerreweighed. It weighs 16.9 N. What is the densityof the weight? [Use g=9.8m/s2.] Hint: The netforce on the bottom of the beaker after the weight is lowered tothe bottom is (the weight of the reduced volume of water) + (300 gweight).

Thebeaker is refilled to the top with water and a 100 g piece of woodof density 0.8 that of water is carefully floated on the water.What volume of water overflows?


NOTE: The claim is that melting of Arctic sea-ice, including largeicebergs, does NOT increase sea-level, but that melting ofGreenland or Antarctic glaciers does increasesea-level.

Why areboth claims made in the NOTE correct?

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How does a newton cradle visually demonstrate how NRG and momentum are conserved. I konw it...

How does a newton cradle visually demonstrate how NRG and momentum are conserved. I konw it works mathematically but how does releasing balls and having the other two balls on the other side swing up demonstrate momentum and conservation of NRG.

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6. One morning while waiting for class to begin, you are reading a newspaper article about...

6. One morning while waiting for class to begin, you are reading a newspaper article about airplane safety. This article emphasizes the role of metal fatigue in recent accidents. Metal fatigue results from the flexing of airframe parts in response to the forces on the plane especially during take off and landings. As an example, the reporter uses a plane with a take off weight of 200,000 lbs and take off speed of 200 mph which climbs at an angle of 30o with a constant acceleration to reach its cruising altitude of 30,000 feet with a speed of 500 mph. The three jet engines provide a forward thrust of 240,000 lbs by pushing air backwards. The article then goes on to explain that a plane can fly because the air exerts an upward force on the wings perpendicular to their surface called "lift." You know that air resistance is also a very important force on a plane and is in the direction opposite to the velocity of the plane. The article tells you this force is called the "drag." Although the reporter writes that some metal fatigue is primarily caused by the lift and some by the drag, she never tells you their size for her example plane. Luckily the article contains enough information to calculate them, so you do.

1. Focus (on) the Problem.

2. Describe the Physics

3. Plan a Solution

4. Execute Your Plan

5. Evaluate the Answer

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(a) How many fringes appear between the first diffraction-envelope minima to either side of the central...

(a) How many fringes appear between the first diffraction-envelope minima to either side of the central maximum in a double-slit pattern if λ = 699 nm, d = 0.200 mm, and a = 36.9 µm? (b) What is the ratio of the intensity of the third bright fringe to the intensity of the central fringe?

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