Questions
A plastic sphere floats in water with 45.0% of its volume submerged. This same sphere floats...

A plastic sphere floats in water with 45.0% of its volume submerged. This same sphere floats in glycerin with 35.8% of its volume submerged.

(a) Determine the density of the glycerin.
kg/m3

(b) Determine the density of the sphere.
kg/m3

In: Physics

An object is placed in front of a diverging lens with a focal length of 17.1...

An object is placed in front of a diverging lens with a focal length of 17.1 cm. For each object distance, find the image distance and the magnification. Describe each image.

(a) 34.2 cm

location cm magnification

(b) 17.1 cm

location cm magnification

(c) 8.55 cm

location cm magnification

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A house has 140m^2 of wall area with a thickness of 30cm, and glass area of...

A house has 140m^2 of wall area with a thickness of 30cm, and glass area of 8m^2 with a thickness of 0.5cm. Given thermal conductivity of wall =0.69 W/mK and thermal conductivity of glass = 0.78 W/mK. If these are the only mechanisms for heat loss from the house, estimate the rate of heat loss when the inside temperature is 20 degrees C and the outside temperature is -10 degrees C.

PART B: If the house is heated with an oil burner with 80% efficiency how many gallons of oil will be required each day to heat the house?(Assuming 140,000 BTU/gallon)

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Explain briefly what excimer lasers are and the reason why they are used in photorefractive keratectomy,...

Explain briefly what excimer lasers are and the reason why they are used in photorefractive keratectomy, in which the front of the cornea is sculpted to correct nearsightedness.

-Why is the argon ion laser not a good choice for this operation?

-Why is the reverse true for laser surgical procedures performed on the retina?

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A pair of narrow slits is positioned 1.90 m from a screen and illuminated with light...

A pair of narrow slits is positioned 1.90 m from a screen and illuminated with light made up of two wavelengths 556.00 nm and 507.60 nm.

First a filter is used to block the 507.60 nm light from reaching the screen.  The resulting interference maxima are found to be separated by s = 1.60 mm.

a) What is in meters the separation of the slits?
We now remove that filter and place a filter that blocks the 556.00 nm light.

b) What is in mm the obtained fringe separation?

We remove both filters.

c) What is in meters the separation on the screen of first bright maxima due to both wavelengths?

d) What is in meters the separation on the screen of fourth bright maxima due to both wavelengths?

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Is the "gas" of free electrons in a metall all electrons in the metall? If not,...

Is the "gas" of free electrons in a metall all electrons in the metall? If not, which ones are in the "gas"?

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Alice is moving wit 0.8c towards a mirror. She sends a light pulse towards the mirror...

  1. Alice is moving wit 0.8c towards a mirror. She sends a light pulse towards the mirror when she is at a distance L from the mirror. Bob is at rest with respect to the mirror and is observing this experiment. After how long will Alice receive the reflected pulse, as measured by Alice and Bob?

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A 21500 kg jet airplane is flying through some high winds. At some point in time,...

A 21500 kg jet airplane is flying through some high winds. At some point in time, the airplane is pointing due north, while the wind is blowing from the north and east. If the force on the plane from the jet engines is 35500 N due north, and the force from the wind is 14700 N in a direction 75.0° south of west, what will be the magnitude and direction of the plane's acceleration at that moment? Enter the direction of the acceleration as an angle measured from due west (positive for clockwise, negative for counterclockwise).

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Where did the atoms that make up a newborn baby originate?

Where did the atoms that make up a newborn baby originate?

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A block of mass m1 = 2kg is placed on a 30 degree incline. The block...

  1. A block of mass m1 = 2kg is placed on a 30 degree incline. The block is attached to a string that passes over a pulley at the top of the incline. vertically from a string that passes over a pulley. A mass m2 = 0.2kg is hanging from the other end of the string. If the coefficients of static and kinetic friction are us = 0.4 and uk = 0.3,
    1. Will the system accelerate if it’s initially at rest? Justify your answer with physics!
    2. If it does accelerate, what is the acceleration? In which direction is this acceleration?
    3. What is the value of m2 that will cause the system to be stationary if friction is negligble?

In: Physics

Which muscle has the biggest advantage? which one Brachioradialis Biceps Brachialis

Which muscle has the biggest advantage? which one

Brachioradialis

Biceps

Brachialis

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The cylinder in the figure(Figure 1) has a moveable piston attached to a spring. The cylinder's...

The cylinder in the figure(Figure 1) has a moveable piston attached to a spring. The cylinder's cross-section area is 10 cm2, it contains 0.0040mol of gas, and the spring constant is 1500 N/m. At 19 degreesC the spring is neither compressed nor stretched.

How far is the spring compressed if the gas temperature is raised to 200 degrees C ?

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A package of dishes (mass 50.0 kg) sits on the flatbed of a pickup truck with...

A package of dishes (mass 50.0 kg) sits on the flatbed of a pickup truck with an open tailgate. The coefficient of static friction between the package and the truck's flatbed is0.340, and the coefficient of kinetic friction is 0.180.


(a) The truck accelerates forward on level ground. What is the maximum acceleration the truck can have so that the package does not slide relative to the truck bed?

(b) The truck barely exceeds this acceleration and then moves with constant acceleration, with the package sliding along its bed. What is the acceleration of the package relative to the ground?

(c) The driver cleans up the fragments of dishes and starts over again with an identical package at rest in the truck. The truck accelerates up a hill inclined at 10.0

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Collision derivation problem. A car is released from rest on a frictionless inclined plane (Figure 5.3)....

Collision derivation problem. A car is released from rest on a frictionless inclined plane (Figure 5.3). EXAMPLES: Calculate the momentum pi at the end of the plane in terms of the measured quantities x, y, L, and m. Assume is very small so that h/L is approximately equal to y/x. (Hint: use conservation of energy and the fact that K=1 2mv2=p2 2m.)
[Answer: .]
If a car suffers a nearly elastic collision it will coast back up the ramp a distance Lf before reversing direction. What is the momentum pf immediately following the collision? The general expression for the change in momentum suffered in a collision is is = - . What is p (the magnitude of ) in terms of x, y, Li, Lf, and m?
[Answer: .]
This is the expression you should use in the experiment. Make sure you understand how to derive these equations.
QUESTION:
If the car has a mass of 0.3 kg, the ratio of height to width of the ramp is 11/110, the initial displacement is 1.8 m, and the change in momentum is 0.62 kg*m/s, how far will it coast back up the ramp before changing directions?

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A window washer weighing 788.3 N is standing on a scaffold supported by a vertical rope...

A window washer weighing 788.3 N is standing on a scaffold supported by a vertical rope at each end. The scaffold weighs 294.9 N and is 5.486 m long. What is the force in each rope when the window washer stands 1.62 m from one end?  

In: Physics