Two long thin parallel wires 13.0 cm apart carry 25-A currents in the same direction.

Part A

Determine the magnitude of the magnetic field vector at a point 10.0 cm from one wire and 6.0 cm from the other (Figure 1) .

Express your answer using two significant figures. B=?

Part B

Determine the direction of the magnetic field vector at that point.

Express your answer using two significant figures.

A particular make of light bulb contains argon at 50 Torr and has a tungsten filament of radius 0.10mm and length 5.0cm. When operating, the gas close to the filament has a temperature of about 1000°C. How many collisions are made with the filament in each second.

Q: Do resonance positions get harder to find lower down in the tube?

Note: this is a questions based on a physics lab revolved around the idea of sound waves and the measurement of the velocity of sound in an air at room temperature and understanding the meaning of longitudinal or compressional waves. A synopsis of the lab: basically we used a long glass tube filled with water and attached to the apparatus was a reservoir in which as we brought lower to the ground water would fill it and the water in the tube would decrease, a sound of a certain frequency using a speaker would be continuously playing directly down the tube from the mouth and we had to tick off 5 times the depth in when we would hear the sound frequency change as the water level was lowered.

Thanks for helping!

In your opinion, what are the primary limitations to the accuracy of outdoor air-temperature sensors, and what could be done to reduce these limitations?

A square insulating sheet 90.0 cm on a side is held horizontally. The sheet has 8.50 nC of charge spread uniformly over its area.

1.Calculate the magnitude of the electric field at a point 0.100 mm above the center of the sheet.

2.Estimate the magnitude of the electric field at a point located a distance 200 m above the center of the sheet.

E = 5.46×10−5 N/C
E = 2.39×10−4 N/C
E = 1.91×10−3 N/C
E = 2.68×10−2 N/

3. Would the answers to parts A and B be different if the sheet were made of a conducting material? Select the correct answer and explanation.

The charge would automatically spread out evenly over both faces, giving it half the charge density on either face as the insulator and the same electric field only close to the sheet. The answer to part A would not change, but the answer to part B would change.
The charge would automatically spread out evenly over both faces, giving it half the charge density on either face as the insulator and changing the sign of the electric field. Both answers would change.
The charge would automatically spread out evenly over both faces, giving it half the charge density on either face as the insulator and changing the electric field. Far away, they both look like points with the same charge. The answer to part B would not change, but the answer to part A would change.
The charge would automatically spread out evenly over both faces, giving it half the charge density on either face as the insulator but the same electric field. Far away, they both look like points with the same charge. Neither answer would change.

A small sphere with mass 2.10 g hangs by a thread between two large parallel vertical plates 5.00 cm apart (Figure 1). The plates are insulating and have uniform surface charge densities +σ and −σ. The charge on the sphere is q = 8.30×10⁻⁶ C .

What potential difference between the plates will cause the thread to assume an angle of 30.0∘ with the vertical?

Consider the head-on collision between a water molecule, mass 18u and a nitrogen molecule mass 28u. Prior to the collision, the nitrogen moving to the right at +0.4390 km/s and the water molecule is moving to the left at -0.7570 km/s. Immediately after the collision, the velocity of the water molecule is v = 0.6990 km/s. A positive sign indicates a molecule moving to the right and a negative sign indicates a molecule moving to the left. The atomic mass unit (u) is commonly used to indicate the mass of atoms and molecules: 1u=1.66×10^-27kg.

What is the velocity of the nitrogen molecule immediately after the collision? (in m/s)

If the collsion described above is an elastic collision, which of the following MUST conserved?
I. Momentum
II. Kinetic Energy

Explain in words and complete sentences the physical meaning of each of Newton's three laws of motion. Note: Do not simply restate or paraphrase the statements of these laws in your textbook. You must actually explain with suitable examples what the textbook statements mean physically.

A mirror faces a cliff located some distance away. Mounted on the cliff is a second mirror, directly opposite the first mirror a distance 1,772.35 away and facing toward it. A gun is fired very close to the first mirror. The temperature on the day is 26.88 oC. How many times does the muzzle flash of the gun travel the round trip distance between the mirrors before the echo of the the gunshot is heard?

A skateboarder starts up a 1.0-m-high, 30? ramp at a speed of 7.2m/s . The skateboard wheels roll without friction. At the top, she leaves the ramp and sails through the air.

How far from the end of the ramp does the skateboarder touch down?

Diffraction is defined as the bending and spreading of waves around small items, slits, or corners. Sound exhibits diffraction just as light does. In your initial discussion post, address the following:

• Identify two everyday phenomena that exhibit diffraction of sound and explain how diffraction of sound applies.
• Identify two everyday phenomena that exhibit diffraction of light and explain how diffraction of light applies.
• Comparing your examples, what are some significant differences between diffraction of light and diffraction of sound, if any?

identify the pros and cons of using mirrors versus lenses in each of the following applications:

• a large, ground-based, astronomical telescope
• a small “spy” scope
• a terrestrial telescope designed only to read license plates

A physics student who weighs 516.0  N stands on a bathroom scale in an elevator that is supported by an elevator cable; the mass of the elevator, including the student inside, is 868.0  kg . While the student is standing on the scale, the elevator makes an upward trip, followed by a downward trip.

A)Find the magnitude of the acceleration of the elevator at the instant of time when the scale reads 449.0  N

B)What is the tension in the elevator cable in Part (A)?

When the Scale Reads More than the Weight of the Student

At some time during her elevator ride, the scale reads 686.0  N .->>

->> C)What is the magnitude of the acceleration of the elevator if the scale reads 686.0  N ?

D)In which direction is the elevator moving if the scale reads 686.0  N ?