Two blocks connected by a string are pushed across a horizontalisurface by a force applied to one of the blocks as, shown in the figure. The coefficient of kinetic friction between the blocks and the surface is 0.20. If, F 20 N and M1.5 kg, what is the tension in the connecting, string?

Monica and Dylan are doing a “thought experiment”. They are imagining that Monica is in a space ship orbiting a black hole, just outside the event horizon, while Dylan is in a space ship 1 light year away. Monica and Dylan each send each other a signal using a laser. From each of their perspectives, their laser flashes once a second. To Dylan, is Monica’s laser flashing faster, slower or at the same rate (once a second)? Similarly, how fast does Dylan’s laser appear to be flashing from Monica’s point of view?

An electrically neutral penny is charged by induction to +5.5 LaTeX: \muμC. After charging, is the penny now more massive or less massive, and what is its change in mass? Group of answer choices

More massive, 3.4E13 kg

Less massive, 3.1E-17 kg

More massive, 3.1E-17 kg

Less massive, 3.4E13 kg

More massive, 3.1E-12 kg

a) How is charge transferred in the process of friction?

b) How is charge transferred in the process of direct contact?

c) How is charge transferred in the process of inductance?

d) How can a charged object attract a neutral object?

Please type your responses.

Two air track gliders of mass 400.0 g and 300.0 g are moving towards each other in opposite directions with speeds of 60.0 cm/s and 100.0 cm/s, respectively. Take the direction of the more massive glider as positive. Use units of "g" and "cm/s" in your calculations.

1. Determine the velocity of each glider after the collision if the collision is elastic. (Use units of "g" and "cm/s" for this question.)
2. The most "inelastic" collision would occur if the two gliders stuck together on impact. If this was the case, find the velocity of the pair after the collision, and the kinetic energy lost as a result of the collision. (Determine the energies in standard units of "J.")

Question 1 Part A

If at a certain point in time the displacement is positive for an object moving under simple harmonic motion, what is the sign of its acceleration?

Part B

For an object in simple harmonic motion, what is the length of time required to return to its original position and to be traveling in the original direction?

Part C

For an object moving under simple harmonic motion while attached to a spring, when is the speed the greatest?

Part D

A spring is hanging motionless from the ceiling of a room on the earth. You attach a mass to the end of the spring and after releasing the mass, you observe that the spring extends a distance before momentarily coming to a halt. What then must be the distance below just the spring's equilibrium position to the new equilibrium position of the spring-mass system?

Part E

A block is attached to a spring and is hanging downward motionless from the ceiling of a room on the earth. Is the spring in equilibrium?

Part F

For an object moving under simple harmonic motion while attached to a spring, when is the net force zero?

Part G

What is the term for the object's maximum possible displacement when moving under simple harmonic motion?

Part H

A spring is hanging downward from the ceiling of a room on the earth, has nothing attached to the end, and is motionless. Is the spring in equilibrium?

Part I

For an object moving under simple harmonic motion while attached to a spring, when is the speed zero?

Part J

For an object moving under simple harmonic motion while attached to a spring, when is the net force the greatest?

In an (AC) RLC circuit, does the what is the order of obstruction? Does the inductor, capacitor, or resistor obstruct first? and last? And what are each of them obstructing ( change of current or change of voltage)?

What about in (DC) source?

What happens when the capacitor receives a change in rate of voltage? Does it induce a new current to push back the voltage? I am very confused.

Please show in detail and diagrams.

Thank you

if a galaxy is tilted 45 degrees to my line of sight then how much does the wavelength of 21 cm shift when you move from the center to the edge of galaxy given a orbital speed of 220 km/s?

A (cube, with a calculable volume of dimensions Xm=7 x Ym=7 x Zm=7), having density rho=80 kg/m³, is 80% (less than 100%) submerged in a fluid having density rho_fluid=1500 kg/m³. Find a) the tension in a string holding the object to the bottom of container holding the fluid (aside; this only makes sense if the buoyancy force exceeds the object's weight force), and b) the numerical value of the pressure at the top and the bottom of the object, including atmospheric pressure. Remember that: a) the buoyancy force depends only on the submerged volume, rather than the total volume of the object, and b) atmospheric pressure is 101325 pascal (Pa).

A bar magnet falls freely, with its north pole pointing straight down. It approaches and passes through a fixed, horizontally orientated, metal ring.

a) How, if in any way, is the magnet's motion affected as it approaches the ring?

b) How, if in any way, is the magnet's motion affected as it leaves the ring?

Explain briefly with appropriate diagrams showing induced currents and their magnetic effects.

Given the Ising model or a canonical ensemble how is the critcal temperature calculated?

Also, would you happen to know the relationship between how many neighbor interactions there are and how this affects temperature?

thanks!

10.A 12.3 kg child jumps up and grabs a (round) horizontal tree branch that has a diameter of 6 cm. The child grabs the branch 28 cm from the trunk, and the weight of the child causes the branch to sag. If the shear modulus for the tree is 1.016 x 10^6N/_m2, how how much does the branch sag when weighted?

11.Ropes for rock climbing have a diameter of 10.5 mm and a Young's modulus of 8.72x10⁷ N/m². If a rock climber of mass 82.4 kg falls when there is 45.8 m of rope out, how far will the rope stretch?

A 3kg object is attached to spring and will stretch the spring 392mm by itself. There is no damping in the system and a forcing function of F(t)=10 coswt, w=(k/w)^-2 is attached to the object. The spring is deflected y distance father than equilibrium position due to the F(t). k is the spring modulus and M is the mass of the object.

a) Derive the governing equation for the spring-object mass system decribed in the problem.Assume Mg=hk

b) if the object is initially displaced 20cm downward from its equilibrium position and given a velocity of 10cm/s upward find the displacement of the object at any time t.

c) suppose a damper is added to the mass-spring system that will exert a force of 45N when the velocity is 50cm/s, damping factor of 90kg/s is added to the system. And find the displacement of the object at any time t for this new system

d)Determine the amplitude , nature frequency and phase shift of the object for this new system.

(a) A particle is dropped (from radius a with zero velocity) into the gravitational potential corresponding to a static homogeneous sphere of radius a and density ρ. Calculate how long the particle takes to reach the other side of the sphere. [Hint: the equation of motion is d²r/dt² = −GM(r)/r² .]

(b) Calculate the time required for a homogeneous sphere of radius a and density ρ with no internal pressure support to collapse to zero radius under its own gravity. [Apply the previous equation of motion to a particle on the surface.]

1a Describe how thermal energy is obtained by fission, specifically when a U=235 atom is hit by a slow-motion neutron (less than 0.9 MeV). When one states that 200 MeV of energy are released by a fission event, what is the form of this energy?

1b. The energy released by fission is by the change in mass and Einstein’s equation (E=Δmc²). If the mass of one uranium 235 atom is 235.042924 amu and the mass of fission products is 234.92754 amu, determine the energy in Joules and MeV released by one fission. (Note: 1 amu = 1.66 x 10^-27kg and 1 ev = 1.6 \x 10^-19J).

1c. For an atom, the atomic number is the number of protons, while the atomic weight (i.e. molecular weight) can be 235 or 238 depending on the isotope. Determine the number of atomic particles (electrons, neutrons, and protons) for U-235, U-238, Kr-90. Note: The atomic number of Krypton is 36.