Often times during volcano eruptions the clouds have large static charge buildups that cause lightning to happen. If a rock is ejected by the volcano and it flies to a height of 1795 m, and the clouds have a charge concentration of +40.0 C at a height of 3400 m and ?40.0 C at a height of 1000 m, what is the electric field at the ejected rock?

A spring with spring constant 20 N/m hangs from the ceiling. A ball is attached to the spring and allowed to come to rest. It is then pulled down 8.5 cm and released. The ball makes 28 oscillations in 18 s seconds.

A) What is its the mass of the ball?​

B) What is its maximum speed?​

The free oscillations of a mechanical system are observed to have a certain angular frequency ?₁. The same system, when driven by a force F₀cos?t, has a power resonance curve whose angular frequency width, at half-maximum power, is ?₁/5.

(a) At what angular frequency does the maximum power input occur?

(b) What is the Q of the system?

(c) The system consists of a mass m on a spring of spring constant k. In terms of m and k, what is the value of the constant b in the resistive term -bv?

At a steam power plant, steam engines work in pairs, the heat output of the first one being the approximate heat input of the second. The operating temperatures of the first are 770 ∘C and 460 ∘C, and of the second 435 ∘C and 280 ∘C.

A) If the heat of combustion of coal is 2.8×107J/kg, at what rate must coal be burned if the plant is to put out 860 MW of power? Assume the efficiency of the engines is 65% of the ideal (Carnot) efficiency

B)Water is used to cool the power plant. If the water temperature is allowed to increase by no more than 4.5∘C, estimate how much water must pass through the plant per hour.

A converging lens of focal length 20.0 cm forms images of an object situated at various distances. (a) If the object is placed 40.0 cm from the lens, locate the image, state whether it's real or virtual, and find its magnification. (b) Repeat the problem when the object is at 20.0 cm and (c) again when the object is 10.0 cm from the lens. (d) Follow through with ray tracing.

And Repeat the above problem, but now for a diverging lens of focal length 10.0 cm. Similarly, draw a ray trace to show the effect of a diverging lens.

Consider each of the following systems for long times, at which their behacioor is time invariant. Identify each system as equilibrium or steady state.

1) A hose supplies water at a constant rate to a bucket with a hole in it. A constant water level is maintained

2)A mixture of reacting gas molecules is constrained to a fixed temperature, e.g., H2, O2 and H2O at 600 K.

3) Ice floats in water, thermally insulated from its surroundings.

4) Molten steel is poured into a continuous casting mill while withdrawing solid steel from the bottom.

(5) A foil birthday balloon is brought into a hot room.

A 0.59 kg object connected to a light spring with a force constant of 19.2 N/m oscillates on a frictionless horizontal surface. If the spring is compressed 4.0 cm and released from rest.

(a) Determine the maximum speed of the object.
cm/s
(b) Determine the speed of the object when the spring is compressed 1.5 cm.
cm/s
(c) Determine the speed of the object when the spring is stretched 1.5 cm.
cm/s
(d) For what value of x does the speed equal one-half the maximum speed?
cm

A uniform electric field of magnitude E=270V/m is directed in the positive x direction. A proton moves from the origin to the point (x, y)=(20.0cm, 50.0cm).

a) Through what potential difference does the charge move?

b) What is the change in the potential energy of the charge field system?

c) An electron is released at rest at the origin and it moves in the +x direction. What would be its speed, V_f, after the electron is released from rest and travels distrance d in the uniform E field? Please derive the express of v_f as a function of the given quantities: E, d, e (the elementary charge) and m (the mass of the electron).

World production of crude oil in 2010 was about 3.5 billion tonnes. Assume that we wish to replace 10% of this supply with a transportation fuel derived from biomass. Assume that the energy content of biomass is about 1% of incident solar energy during the growing season. How many hectares of arable land worldwide would be needed to supply this quantity of biomass fuel? What fraction of arable land area worldwide does this represent?

A river has a steady speed of 0.370 m/s. A student swims upstream a distance of 1.00 km and swims back to the starting point.

(a) If the student can swim at a speed of 1.30 m/s in still water, how long does the trip take?
s

(b) How much time is required in still water for the same length swim?
s

(c) Intuitively, why does the swim take longer when there is a current?

The diameter of a nickel is 21 mm .

How far from your eye must it be held so that it has the same apparent size as the moon? (Use the astronomical data inside the back cover of the textbook.)

Beryl (m=45kg) is standing in an elevator that is moving vertically upward at a speed of 3 m/s. 1.5 s later, the elevator and Beryl are moving vertically downward at a speed of 5 m/s. Beryl's feet remain in contact with the elevator's floor at all times, and that is Beryl's only point of contact with the elevator. (The y axis is vertical and positive upward)

What is the y-component of Bery;'s acceleration during that time interval?

What is the magnitude of Beryl's weight?

What is the magnitude of the normal force that the elevator exerts on Beryl during that time interval?

Write a program using multiple functions. Make use of an array to store data Make use of searching techniques Read data from a file Write data to a file Instructions: In this lab, you will be examining a set of stock collected over a twenty four day period. Be sure to make use of an array to store these stocks. You will be required to read in the data points from a file. Write a function to read in the data. (See data details below.) After reading in the data, you will need to write a function that will calculate the average of the data set. You need to define a struct to contain stock investments, gain, etc. Then you should write a function to display the stocks in the table format shown below. Table Format: Hour stock Difference from Avg 1 35 -02.29 2 32 -05.29

A physics student is sitting on a rotating platform. He is holding a heavy weight in each of his outstretched hands. At request of his physics instructor(!) he carries out various manoeuvres to try to change his angular velocity. Which of the following scenarios are described correctly? Select True or False. 1) True False Starting at rest, he drops the weights. His angular velocity decreases. 2) Starting with angular velocity ωgw, he brings the weights in to his chest. His angular velocity reverses. 3) Starting at rest, he brings the weights in to his chest. His angular velocity increases 4) Starting with angular velocity ωgw, he transfers both the weights to one outstretched hand. He then stretches his other hand back out to its original position. His angular velocity (after the manouvre is complete) has decreased. 5) Starting at rest, he brings the weights in to his chest. His angular velocity decreases. 6) Starting with angular velocity ωgw, he transfers both the weights to one outstretched hand. His angular velocity (after the manoeuvre is complete) has reversed. 7) Starting with angular velocity ωgw, he brings the weights in to his chest. His angular velocity increases. 8) Starting with angular velocity ωgw, he transfers both the weights to one outstretched hand. He then stretches his other hand back out to its original position. His angular velocity (after the manouvre is complete) has increased. 9) Starting with angular velocity ωgw, he raises his feet, and points them outwards from the chair as far as he can. His angular velocity increases. 10) Starting with angular velocity ωgw, he transfers both the weights to one outstretched hand. He then stretches his other hand back out to its original position. His angular velocity (after the manouvre is complete) has not changed.