The coldest and hottest temperatures ever recorded in Switzerland are −43.2°F (231 K) and 106.7°F (315 K), respectively. What is the speed of sound in air at each temperature?

v₂₃₁ = 304.4 m/s

v₃₅₁ = 355.5 m/s

Explanation:

The formula used to find the speed of sound in air, at different temperatures is given as follows:

v = v₀ √(T/273)

where,

v = speed of sound at given temperature

v₀ = speed of sound at 0°C = 331 m/s

T = temperature in K

For T = 231 K:

v₂₃₁ = (331 m/s)√(231 K/273 K)

v₂₃₁ = 304.4 m/s

For T = 315 K:

v₃₅₁ = (331 m/s)√(315 K/273 K)

v₃₅₁ = 355.5 m/s

when a device is used in a circuit in which the voltage is 81 v, the current flowing through the device is 3 a. what is the resistance of the device?

a. 27 ω

b. 40.5 a

c. 243 ω

d. 243 a

the correct answer is a. 27

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia