1- What is the maximum voltage that can be applied across a 2.3-kΩkΩ resistor rated at 1414 watt?

Express your answer to two significant figures and include the appropriate units.

2- A certain copper wire has a resistance of 19.0 ΩΩ . At some point along its length the wire was cut so that the resistance of one piece is 7.0 times the resistance of the other.

Determine the length of the short piece.Express your answer using two significant figures.----------- %%of the length of the wire.

3-

Calculate the ratio of the resistance of 11.0 mm of aluminum wire 2.3 mmmm in diameter, to 23.0 mm of copper wire 1.6 mmmm in diameter. The resistivity of copper is 1.68×10−8Ω⋅m1.68×10−8Ω⋅m and the resistivity of aluminum is 2.65×10−8Ω⋅m2.65×10−8Ω⋅m.

Express your answer using two significant figures.

Two stationary positive point charges, charge 1 of magnitude 3.10 nC and charge 2 of magnitude 1.80 nC , are separated by a distance of 42.0 cm . An electron is released from rest at the point midway between the two charges, and it moves along the line connecting the two charges. What is the speed vfinal of the electron when it is 10.0 cm from charge 1?

A box of mass sits on the floor of an elevator. The area of the bottom surface of the box is 0.250 m2. When the elevator is moving upward at a constant speed of 2.00 m/s the pressure the box exerts on the floor is 981 pascal. (Note: One Pascal equals one Newton per square meter; 1 Pa = 1 N/m2). Calculate the pressure the box exerts on the floor while the elevator a. slows uniformly from an upward speed of 2.00 m/s to zero in 3.00 seconds. b. accelerates uniformly from rest to a downward speed of 2.00 m/s in 3.00 seconds. c. slows uniformly from a downward speed of 2.00 m/s to zero in 3.00 seconds. d. is moving downward at a constant speed of 2.00 m/s e. accelerates uniformly from rest to an upward speed of 2.00 m/s in 3.00 seconds f. is at rest.

How effective would a thermonuclear device of 47 megatons or higher like the zsar bomba be in space?

Could we use as planetary defence on somthing like an asteroid as long as it is detected in time and what effect if any would it have on our planet and our satellites in orbit?

A model rocket blasts off from the ground, rising straight upward with a constant acceleration that has a magnitude of 91.3 m/s2 for 1.79 seconds, at which point its fuel abruptly runs out. Air resistance has no effect on its flight. What maximum altitude (above the ground) will the rocket reach?

A device connected in a parallel circuit will undergo a higher voltage drop compared to the same device connected in a series circuit. is this true or false, and also why does this occur?

In two paragraphs, compare and contrast the atmospheres of the inner planets. Explain the important conditions leading to the differences of these atmospheres.

Keep in brief and short. Thank you.

A charge of -2.75 µC is fixed at the center of a compass. Two additional charges are fixed on the circle of the compass, which has a radius of 0.092 m. The charges on the circle are -4.3 µC at the position due north and +5.25 µC at the position due east. What are the magnitude and direction of the net electrostatic force acting on the charge at the center? Specify the direction relative to due east.

Assume you have a somewhat idealized J-band system with spectral response of 0.8 from 1.15 through 1.35 mm and zero outside this range.

What is the effective (mean) wavelength?

Select the situations from the list below in which mechanical energy is conserved.

A ball sliding down a hill with friction.

The Moon orbiting the Earth.

A ball sliding down a frictionless hill.

A child swinging on a frictionless swing, ignoring air resistance.

A ball that is dropped from a certain height and bounces back to a lower height.

An ice skater gliding along the ice.

Someone else posted this but the answer isn't correct.

You are an astronaut in the space shuttle pursuing a satellite in need of repair. You are in a circular orbit of the same radius as the satellite (420 km above the Earth), but 24 km behind it.

(a) How long will it take to overtake the satellite if you reduce your orbital radius by 1.0 km?

___________ hr

(b) By how much must you reduce your orbital radius to catch up in 7.0 hours?
___________ m

a property company who will also operate the building is deciding whether to build a standard efficiency office building or a high efficiency office building. The office building is 8,000 m2 and its energy is supplied 100% by electricity. The standard efficiency office tower will consume approximately 140 kWh / m2 /y. The high efficiency office tower will consume approximately 100 kWh / m2 /y. The incremental cost (i.e. the cost between the standard efficiency and high efficiency office tower) is $40 per m2 and the building systems are expected to last 25 years. 8a. What is the estimated annual energy cost savings per year for the high efficiency building compared to the standard efficiency building? o 8b. Does it make sense for the property company to invest in the high efficiency office building?

1) Picture a Styrofoam packing peanut in your hand. If you close your hand around it and squeeze, what are you doing to the pressure?

2) How does this affect the volume of the packing peanut?

3)By this example, what is the relationship between the pressure on an object and the volume of the object (direct relationship, inverse relationship, etc.)? Explain how you come to this conclusion.

4) Now let

Unit 2 Accelerations ...
Compute the answers and match the following.