Answer:
The magnetic force is 0.3 N.
Explanation:
Given that,
Current in an unusual lightning strike, I = -400 A
The Earth’s magnetic field at that location is parallel to the ground and has a magnitude of 30 μT,
We need to find the force exerted by the Earth’s magnetic field on the 25 m-long current.
The magnetic force is given by :
So, the magnetic force is 0.3 N.
To solve this problem it is necessary to apply the rules and concepts related to logarithmic operations.
From the definition of logarithm we know that,
In this way for the given example we have that a logarithm with base 10 expressed in the problem can be represented as,
We can express this also as,
By properties of the logarithms we know that the logarithm of a power of a number is equal to the product between the exponent of the power and the logarithm of the number.
So this can be expressed as
Since the definition of the base logarithm 10 of 10 is equal to 1 then
The value of the given logarithm is equal to 6