What is the center of mass of the ammonia molecule? This molecule has the chemical formula NH3. It is comprised of one nitrogen atom and three hydrogen atoms. The hydrogens are positioned at the corners of an equilateral triangle (with side length 0.16 nm) which forms the base of a pyramid. The nitrogen atom is at the apex of this pyramid, a vertical distance of 0.037 nm above the plane of the equilateral triangle. The lengths and distances in this question have been given in nanometres or nm, where 1 nm = 1 × 10?9 m.

what is quantum scattering?

The diagram below is a top-down view of two children pulling a 11.1-kg sled along the snow. The first child exerts a force of F1 = 10 N at an angle θ1 = 45° counterclockwise from the positive x direction. The second child exerts a force of F2 = 8 N at an angle θ2 = 30° clockwise from the positive x direction.

Identify and describe the steps of the scientific method.
Identify general trends in a data plot.
Convert between SI and American units, as well as within units of the same system (i.e., from feet to miles).
Use kinetic/mathmatical equations to find acceleration, velocity, position, or time.
What sre Newton’s three laws of motion.
How to Add vectors, including vectors that represent forces and velocity.
Explain the difference between weight and mass.
Explain the concept of conservation of linear and angular momentum and its applications.
Formula to Apply impulse with conservation of momentum.

You have discovered a new galaxy and you think you have identified an Type II Cepheid star with a period of 30 days. You measure its brightness and with the Period-Luminosity function you calculate the distance to the galaxy d. However, you later find out that in fact the star you had identified is a Type I Cepheid. Is the galaxy further than, or, close to, us than we previously expected? By what factor should you multiply d to get the correct distance to the new galaxy? [Hint: check the diagram in the slides for the Distance Ladder lecture]

A Gaussian surface in the form of a hemisphere of radius R = 9.86 cm lies in a uniform electric field of magnitude E = 7.16 N/C. The surface encloses no net charge. At the (flat) base of the surface, the field is perpendicular to the surface and directed into the surface. What is the flux through (a) the base and (b) the curved portion of the surface?

A 12.0-kg block is pushed across a rough horizontal surface by a force that is angled 30.0◦ below the horizontal. The magnitude of the force is 75.0 N and the acceleration of the block as it is pushed is 3.20 m/s2 . What is the magnitude of the contact force exerted on the block by the surface?

One possibility for a low-pollution automobile is for it to use energy stored in a heavy rotating flywheel. Suppose such a car has a total mass of 1100 kg, uses a uniform cylindrical flywheel of diameter 1.50 m and mass 240 kg, and should be able to travel 350 km without needing a flywheel �spinup.� (a) Make reasonable assumptions (average frictional retarding force = 450 N, twenty acceleration period from rest to 95 km/h, equal uphill and downhill, and that energy can be put back into the flywheel as the car goes downhill), and estimate what total energy needs to be stored in the flywheel. (b) What is the angular velocity of the flywheel when it has full �energy charge�? (c) About how long would it take a 150 hp motor to give the flywheel a full energy charge before a trip?

A projectile of mass m = 5kg is thrown upward vertically with a velocity v₀ = 9 m/s

a) Starting with Newton's 2nd Law F_Net = ma, calculate the time to an accuracy of four decimal places at which the maximum height is reached when no air resistance is present.

b) Starting with Newton's 2nd Law F_Net = ma, calculate the time to an accuracy of four decimal places at which the maximum height is reached when considering the following force of air resistance:

F_air = 7.775 x 10^-5v

c) Starting with Newton's 2nd Law F_Net = ma, calculate the time to an accuracy of four decimal places at which the maximum height is reached when considering the following force of air resistance:

F_air = 0.055v²

A 78.0 kg hoop rolls along a horizontal floor so that its center of mass has a speed of 0.190 m/s. How much work must be done on the hoop to stop it?

When a DC current passes through the coil, it will produce a magnetic flux around the coil. Is this the reason why the coil get heated? Because the magnetic flux will be stable after all as DC current does not oscillate?

The deuteron is a bound state of a proton and a neutron of total angular momentum j = 1. It is known to be principally an S(ℓ = 0) state with a small admixture of a D(ℓ = 2) state. Calculate the magnetic moment of the pure d state n-p system with j = 1. Assume that the n and p spins are to be coupled to make the total spin s which is then coupled to the orbital angular momentum ℓ to give the total angular momentum j. Express your result in nuclear magnetons. The proton and neutron magnetic moments are 2.79 and -1.91 nuclear magnetons, respectively.
Note: The nuclear magneton is given by
µ = [(gℓℓ + gss) · j] j(j + 1) jµ0

2 questions thx

1) A point source emits sound waves isotropically. A sound meter measures a sound level of 51.72 dB at location C and a sound level of 45.53 at location D, a distance of 16 m from location C. The two locations C and D and the point source are all located along the same line. How far from location C is the point source? Give your answer in m, though enter only the numerical part in the box.

2) A point source emits sound waves isotropically. A sound meter measures a sound level of 51.21 dB at location C and a sound level of 47.79 at location D, a distance of 15 m from location C. The two locations C and D and the point source are all located along the same line. What is the total output power emitted by the point source? Give your answer in mW, though enter only the numerical part in the box.

A.) What is a power law? What does it mean for a quantity like the electric field to drop off as a power law?

B.) Does the electric field always drop off as r^-2, or can it drop off faster?

C.) Can the Coulomb force do work on a mass? What is required for this to happen?

A helium-filled toy balloon has a gauge pressure of 0.350 atm and a volume of 8.0 liters. How much greater is the internal energy of the helium in the balloon than it would be at zero gauge pressure?__________J

Please show all work to get credit.