A spherical raindrop falling through mist builds up mass. The mass accumlates at a rate proportional to its cross-sectional area and invers;ey proportional to its velocity, that is, dm/dt=k?r2/v, where r is the radius of the raindrop at a given time and v is the downard speed at the same time.Assuming the density P of the rain drop is a constant. Ignoring the resistance do to the fog and the air, calculate the instaneous acceleration of the raindrop as a function of v,r,P,g and k.

Explain charging by contact. How is the charge of the charging object related to the charge of the thing being charged once the charging is complete?

Could you please explain thin film interference and the equations for it I just don't get it. Thank You

Calculate the mass of the sun from the radius of the earth's orbit (1.50×10¹¹ m), the earth's period in its orbit, and the gravitational constant G.

What is the density of the sun ? (The sun's radius is 6.96×10⁸ m). Notice how it compares with the density of the earth.

An electron is accelerated to a speed where its total energy is 226 times larger than its rest energy.

PART 1

How many times is the kinetic energy of the electron larger than its rest energy?

PART 2

What is the kinetic energy of the electron?

PART 3

What is the speed of the electron in terms of the speed of light?
(In this part of the problem you have to enter your answer with a precision of seven or eight digits!)

PART 4

What is the momentum of the electron measured in MeV/c units? (Enter only a number without the MeV/c unit.)

A 7 μC charge is at the origin. Another particle, placed at x = 0.2m feels of force of 11N in the negative x-direction.

a) Find the value of the unknown charge.

b) Find the electric field midway between these two charges.

c) Find the potential midway between these two charges.

d) Find the potential energy of this pair of charges.

As a city planner, you receive complaints from local residents about the safety of nearby roads and streets. One complaint concerns a stop sign at the corner of Pine Street and 1st Street. Residents complain that the speed limit in the area (89 km/h) is too high to allow vehicles to stop in time. Under normal conditions this is not a problem, but when fog rolls in visibility can reduce to only 47 meters. Since fog is a common occurrence in this region, you decide to investigate. The state highway department states that the effective coefficient of friction between a rolling wheel and asphalt ranges between 0.842 and 0.941, whereas the effective coefficient of friction between a skidding (locked) wheel and asphalt ranges between 0.550 and 0.754. Vehicles of all types travel on the road, from small VW bugs with a mass of 595 kg to large trucks with mass 4095 kg. Considering that some drivers will brake properly when slowing down and others will skid to stop, calculate the miminim and maximum braking distance needed to ensure that all vehicles traveling at the posted speed limit can stop before reaching the intersection. Minimu =? Maximum=?Given that the goal is to allow all vehicles to come safely to a stop before reaching the intersection, calculate the maximum desired speed limit. = kmh?.

Now you will need to use your data to calculate velocities and accelerations. Recall that we have discussed average velocity as vavg = Δx/Δt as well as vavg = (vi + vf)/2. We also discussed average acceleration as aavg = Δv/Δt. Using these equations, calculate the instantaneous velocity of your cart at each distance/time data point and the average acceleration between each pair of distance/time data points. When you have completed your calculations, organize your results into a table with four columns: time, position, velocity, and average acceleration.

Two vectors are given by A= 1.5i+6.6j and B= 7.0i+6.2j. Find (1) (A+B)*B and (2) the component of A along the direction of B?

A helium balloon ride lifts up passengers in a basket. Assume the density of air is 1.28 kg/m3 and the density of helium in the balloon is 0.18 kg/m3. The radius of the balloon (when filled) is R = 5.4 m. The total mass of the empty balloon and basket is mb = 121 kg and the total volume is Vb = 0.062 m3. Assume the average person that gets into the balloon has a mass mp = 72 kg and volume Vp = 0.079 m3.

volume of helium in the balloon when fully inflated? :660

magnitude of the force of gravity on the entire system (but with no people)? Include the mass of the balloon, basket, and helium. : 2352

buoyant force on the entire system (but with no people)? Include the volume of the balloon, basket, and helium. :8287

1)What is the magnitude of the force of gravity on each person?

2)What is the magnitude of the buoyant force on each person?

3)How many FULL people can the balloon lift up? (Your answer must be an integer.)

Problem 2.

Mass of Mars- 6.39 x 10^23 kg

Mass of Earth- 5.972 x 10^24 kg

Mass of Sun- 1.989 x 10^30 kg

Distance between earth and sun- 1.496 x 10^11

Distance between earth and mars- 5.46 x 10^7

a) What is the force of gravity on earth due to mars?

b) What is the force of gravity on mars due to earth?

c) What is the force of gravity on earth due to the sun?

d) Why does earth revolve around the sun instead of mars?

A student in our class is confused about the motion of pulses on a long taut spring and has scored zeros on many of the homework problems. Pick two ideas that you think are critical for understanding this topic. State them clearly and describe how you would help your fellow student make sense of these ideas. Note: This is an essay question. Your answer will be judged not solely on its correctness, but for its depth, coherence, and clarity.

Part A) When monochromatic UV light of wavelength 347 nm is sent through a diffraction grating, the first order maximum occurs at 17.9^o. How many lines per cm are in the grating?

Part B) Through what voltage should an electron be accelerated from rest so that it would produce the same interference pattern as this light.

Please answer both parts and show work.