Answer:
Explanation: The equation that relates resistance of tungsten at different temperatures is as follows
R = R₀ [1 + α ∆T] , R₀ is resistance at lower temperature , R is resistance at higher temperature . α is temperature coefficient of resistivity and ∆T is rise in temperature .
Putting the values
170 = 26 [1 + .0045 ∆T]
∆T = 1230.75
lower temperature = 40◦C
higher temperature = 1230 + 40
= 1270◦C
Answer:
a

b

c

d

Explanation:
From the question we are told that
The frequency of the radio station is 
The magnitude of the magnetic field is 
Generally the wavelength is mathematically represented as

Here c is the speed of light with value 
So

=> 
Generally the angular frequency is mathematically represented as

=> 
=> 
Generally the wave number is mathematically represented as
=> 
=> 
=> 
Generally the amplitude of the electric field at this distance from the transmitter is mathematically represented as

=> 
=> 
Answer:
Because here is a number of electrons more applied to the balloon