An American traveler in Kenya carries a transformer to convert Kenya's standard 240 V to 120 V so that she can use some small appliances on her trip. (a) What is the ratio of turns in the primary and secondary coils of her transformer? Np Ns = (b) What is the ratio of input to output current? Iin Iout = (c) How could a Kenyan traveling in the United States use this same transformer to power her 240 V appliances from 120 V?

a) / = 2

b) / = 0.5

c) A Kenyan travelling in the united states will now use the output terminal of the transformer in Kenya as the input terminal in the United States, to step up the voltage from 120 V to 240 V for his devices

Explanation:

Kenya's standard voltage = 240 V

America's standard voltage = 120

using the transformer relationship

/ = /

substituting values, we have

240/120 =  /

/ = 2

b) The power input must be equal to the power output

=

where = input current

= input voltage = 240 V

= output current

= output voltage = 120 V

Transposing the above equation, we get

/ = /

/ = 120/240 = 0.5

c) A Kenyan travelling in the united states will now use the output terminal of the transformer in Kenya as the input terminal in the United States, to step up the voltage from 120 V to 240 V for his devices.

multiple

answer: the exterior temperature of commercial jet planes as they leave the stratosphere and return to the ground increases steadily.

explanation:

the lower most layer of atmosphere is troposphere which extends from 0 to 12 km above the surface of the earth. the temperature initially decreases as distance is increased from the earth's surface. commercial jets fly in lower part of the stratosphere. the stratosphere extends upto 50 km. the temperature in stratosphere starts rising again due to presence of ozone which traps the uv rays.

thus, when the planes leave the stratosphere and return to the ground, the exterior temperature increases steadily.