Answer:
Explanation:
Time can be found by dividing the distance by the speed.
The distance is 45 meters and the speed is 12.5 meters per second.
Divide. Note that the meters, or "m" will cancel each other out.
It will take the dolphin 3.6 seconds to swim a distance of 45 meters are 12.5 meters per second.
Answer:
(a)
(b)
Explanation:
Part (a)
The total length of copper cord L=86.3 m
The cross sectional area A=1.71×10⁻⁶m²
The resistivity of copper p=1.72×10⁻⁸Ω
Thus the resistance of extension cord is
Part (b)
The resistance of trimmer Rt=17.9 ohms
When voltage of 120V is applied then the current I is passing through series circuit is
Thus the voltage across the trimmer is:
Answer:
Explanation:
From the question we are told that
The electric filed is
Generally according to Gauss law
=>
Given that the electric field is pointing downward , the equation become
Here is the excess charge on the surface of the earth
is the surface area of the of the earth which is mathematically represented as
Where r is the radius of the earth which has a value
substituting values
So
Here s the permitivity of free space with value
substituting values