0-9. GREENHOUSE EFFECT
CO2 passes short wave length light (visible) but blocks long wave length
radiation (IR). Explain how adding CO2 to an atmosphere increases the
surface temperature of a planet. Consider the temperature of the sources
of radiation in and out.

Show that angular momentum is conserved for a force law F = kr and find the allowed orbits.

When light with a wavelength of 215 nm is incident on a certain metal surface, electrons are ejected with a maximum kinetic energy of 3.33 × 10 − 19 J. Determine the wavelength of light that should be used to quadruple the maximum kinetic energy of the electrons ejected from this surface.

Consider the three basic quantities of a circuit: voltage (potential difference), current, and resistance.

In general terms, describe each one in your own words and its basic characteristic/property, and can you do an analogy of these quantities with a fluid system, say a stream of water?

Further, since many of you are in the medical field, can you relate a basic circuit and its components to a system of the body, maybe the circulatory system? If, what is the analogy between the basic circuit components to components of the circulatory system?

Please no handwritten or picture respones - only typed replies

Compare and contrast the photon nature of light with the wave nature of light, making sure to address the following properties:

a: color

b: intensity

C: energy

Chapter 08, Problem 024. A block of mass m = 1.30 kg is dropped from height h = 59.0 cm onto a spring of spring constant k = 1130 N/m (see the figure). Find the maximum distance the spring is compressed.

The plane of a rectangular loop of wire with a width of 5.0 cm and a height of 8.0 cm is parallel to a magnetic field of magnitude 0.22 T . The loop carries a current of 6.7 A .

What torque acts on the loop?

What is the magnetic moment of the loop?

What is the maximum torque that can be obtained with the same total length of wire carrying the same current in this magnetic field?

In Example 2.6, we considered a simple model for a rocket launched from the surface of the Earth. A better expression for a rocket's position measured from the center of the Earth is given by y(t) = RE3/2 + 3 g 2 REt 2/3 where RE is the radius of the Earth (6.38 ✕ 106 m) and g is the constant acceleration of an object in free fall near the Earth's surface (9.81 m/s2). (a) Derive expressions for vy(t) and ay(t). (Use the following as necessary: g, RE, and t. Do not substitute numerical values; use variables only.) vy(t) = √ g 2 ​2R E ​(R ( 3 2 ​) E ​+3√ g 2 ​R E ​t)(− 1 3 ​) m/s ay(t) = m/s2 (b) Plot y(t), vy(t), and ay(t). (A spreadsheet program would be helpful. Submit a file with a maximum size of 1 MB.) This answer has not been graded yet. (c) When will the rocket be at y = 4RE? Your response differs significantly from the correct answer. Rework your solution from the beginning and check each step carefully. s (d) What are vy and ay when y = 4RE? (Express your answers in vector form.) vy(t) = m/s ay(t) = m/s2

The intensity of sunlight under the clear sky is 1030 W/m2 . How much electromagnetic energy is contained per cubic meter near the Earth’s surface? The speed of light is 2.99792 × 108 m/s. Answer in units of J/m3 .

What is the maximum radiation pressure that can be exerted by sunlight in space of intensity 3693 W/m2 on a flat black surface? The speed of light is 3 × 108 m/s. Answer in units of Pa.

Starting from rest, a disk rotates about its central axis with constant angular acceleration. In 4.00 s, it rotates 13.2 rad. During that time, what are the magnitudes of (a) the angular acceleration and (b) the average angular velocity? (c) What is the instantaneous angular velocity of the disk at the end of the 4.00 s? (d) With the angular acceleration unchanged, through what additional angle (rad) will the disk turn during the next 4.00 s?

1) Because of the mass involved in constructing and transporting a lander, the first human expedition to Mars will likely be an orbital mission. A geosynchronous orbit seems plausible, allowing astronauts in the spacecraft to have continuous line-of-sight control of rovers on the surface. What is the altitude above the surface of Mars for geosynchronous orbit? You’ll need to do some research to find the mass of Mars and its rotation period.

2) Using the expression for the escape velocity from a planet.
a) Describe the physics that went into your derivation of the escape velocity and list the formula again.
b) Use this formula to calculate the escape velocity of Mars and compare it with Earth. List the sources where you obtained the properties of each planet for your calculation.
c) What insight might you glean from the above calculation on why Mars has a thinner atmosphere than the Earth?

3) Assuming that the outer planets (Saturn, Uranus, and Neptune) are in equilibrium with the solar radiation, calculate the effective surface temperature of these 3 planets and show all intermediate steps. You can assume albedos of 0.5, 0.6, and 0.6, for Saturn, Uranus, and Neptune, respectively. The solar luminosity is 3.83 x 1026 W. How do these temperatures compare with their observed temperatures?

A shell is launched at angle 62° above the horizontal with initial speed 30 m/s. It follows a typical projectile-motion trajectory, but at the top of the trajectory, it explodes into two pieces of equal mass. One fragment has speed 0 m/s immediately after the explosion, and falls to the ground. How far from the launch-point does the other fragment land, assuming level terrain and negligible air resistance?

how might a sonogram tech encounter heat, heat transfer, and/or thermal expansion?

Bubba (m=100kg) and Sally (m=60kg) are playing on a merry-go-round. Treat the merry-go-round as a disk with mass 100 kg and radius 1.3 m. Both Bubba and Salley are at the edge of the disk when the disk is rotating at .25 revolutions per second. Suppse Bubba moves inward so that he is now exactly at the center. Treat the two children as point masses. Assuming there is no external torques or forces,

A) What is the new rotational speed of the merry-go-round?

B) How much work is done? Who, what did this work?

Ice at −14.0 °C and steam at 142 °C are brought together at atmospheric pressure in a perfectly insulated container. After thermal equilibrium is reached, the liquid phase at 50.0 °C is present. Ignoring the container and the equilibrium vapor pressure of the liquid, find the ratio of the mass of steam to the mass of ice. The specific heat capacity of steam is 2020 J/(kg.C°).