An object is undergoing uniform circular motion. True or False: A graph of its position oscillates back and forth, but not with simple harmonic motion.
A.) True
B.) False
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Very large accelerations can injure the body, especially if they last for a considerable length of time. One model used to gauge the likelihood of injury is the severity index ( ?? ), defined as ??=?5/2? . In the expression, ? is the duration of the accleration, but ? is not equal to the acceleration. Rather, ? is a dimensionless constant that equals the number of multiples of ? that the acceleration is equal to. In one set of studies of rear-end collisions, a person's velocity increases by 12.5 km/h with an acceleration of 35.5 m/s2 . Let the +? direction point in the direction the car is traveling. What is the severity index for the collision? ??= How far ? does the person travel during the collision if the car was initially moving forward at 5.70 km/h ? ?= m
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A 335 kg box is pulled 6.00 m up a 30° frictionless, inclined plane by an external force of 5425 N that acts parallel to the plane.
Calculate the work done by the external force.
Calculate the work done by gravity.
Calculate the work done by the normal force.
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An LC circuit like that in the figure below consists of a 3.30-H inductor and an 832-pF capacitor that initially carries a 134-μC charge. The switch is open for t < 0 and is then thrown closed at t = 0. Compute the following quantities at t = 5.00 ms. (a) the energy stored in the capacitor (b) the total energy in the circuit (c) the energy stored in the inductor
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The blood speed in a normal segment of a horizontal artery is 0.184 m/s. An abnormal segment of the artery is narrowed down by an arteriosclerotic plaque to 1/3 of its normal cross-sectional area. What is the difference in blood pressure between the normal and constricted segments of the artery?
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My question is little bit philosophical. I would like to explain my ideas with a 2 dimensional universe model.
If we had lived in 2 dimensional universe like a plane, What could we observe when seeing a 3d object?
For example: If a square pyramid that is inside full of material comes to the plane universe in right angle, what could the people who live in 2d universe observe? Firstly, we could see small square and slowly it would enlarge and then it would dissappear suddenly. If the scientists who live in the 2d universe observed such event , All scientists could get shocked and they could check their physics formulas because energy is not conversed in that event. They had believed that Energy is conserved and nobody could create energy from nothing and finally they could understand that total observed universe energy can be much more what they calculated with their formulas.
My questions:
What could we see a 4d pyramid comes to our 3d universe? is it correct that Firstly we would see small cube and it would enlarge and then suddenly disappears?
Dark matter and Dark energy is related with such ideas? http://map.gsfc.nasa.gov/universe/uni_matter.html
I know we do not observe such strange events till now but maybe scientists can get some results during micro experiments. Is there any such experimental results at least in micro universe (atomic level experiments in quantum mechanics)?
Sorry for your time if it was asked before.
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Two positive charges of 1.5e-10 C are placed on the x axis at distances +12 cm and -12 cm from the origin, respectively. A third positive charge of 5e-11 C can be moved along the y axis. At what value of y the electrostatic force on the third charge is maximal?
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A tennis player hits a ball 2.0 m above the ground. The ball leaves his racquet with a speed of 16.0m/s at an angle 4.5? above the horizontal. The horizontal distance to the net is 7.0 m, and the net is 1.0 m high.
By how much?
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Kindly answer both questions 1 abd 2 fully.
Question 1) Find the dispersion relation for one
dimensional diatomic lattice?
(definition and difference of optical branch and acoustical
branch)
Question 2) Find the displacement u(x,t) for one dimensional
diatomic lattice?
Kindly answer both questions 1 abd 2 fully.
In: Physics
Consider a rock that is thrown off a bridge of height 85 m at an angle ? = 23
In: Physics
True or False , explain why
Light travels faster in vacuum than it does in a
glass.
When light enters a medium with a higher index of refraction, the ray is bent farther away from the line normal to the boundary.
The path of a ray of light between two points is the path that minimizes the travel time.
White light that is reflected from a surface will be separated into a visible spectrum.
If one stands by a swimming pool, a person standing in the pool will seem to have long legs.
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The cosmic microwave background (CMB) matches a 2.7 K blackbody spectrum extremely well. For a space telescope observing the CMB with an efficient detector with a collecting area of 0.01 m2, estimate (i) the wavelength at which the CMB peaks in intensity, (ii) the power in watts of CMB photons collected by the detector and (iii) the number of CMB photons per unit volume in the vicinity of the space telescope.
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A woman can read the large print in a newspaper only when it is at a distance of 62 cm or more from her eyes. (a) Is she nearsighted (myopic) or farsighted (hyperopic), and what kind of lens is used in her glasses to correct her eyesight? (b) What should be the refractive power (in diopters) of her glasses (worn 2.9 cm from the eyes), so she can read the newspaper at a distance of 29 cm from the eyes?
A: I know she's farsighted
B: I did (1/ 29-2.9 + 1/(62-2.9) = .05523 x 100 = 5.52 cm, which was wrong. How do I solve this part of the equation?
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3. A ski jumper starts from the top of a frictionless track making a 60° angle with the ground. The starting point is 25.0-m above the ground, and the jumper is launched from the upturned end of the track 3.00-m above the ground at an angle of 60°.
a) What is her speed as she leaves the jump?
b) How far away from the track does the jumper land?
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at the same diameter, an air bubble rises faster in liquid faster than a sand pebble falls in liquid water. The densities of air water and sand are 1.2,1000,2500 kg/M3 respectively.
Answer True of False whether or not the air buble travels faster. Need help don't understand the theory behind this question
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