Answer:
6692J
Explanation:
Power is defined as the rate at which work is being done.
So,
Power = 
Work done = Power x time
Given parameters:
Power = 478watts
Time = 14s
So;
Work done = 478 x 14 = 6692J
Answer:
In the middle of a dry cell, is a rod made of carbon. Around the carbon rod is a chemical paste. At the same time, the carbon rod becomes positively charged. When this happens, electrical current flows out of the cell when a conductor is attached between the cell's positive and negative terminals.
NOTE: The given question is incomplete.
<u>The complete question is given below.</u>
A student measures the speed of yellow light in water to be 2.00 x 10⁸ m/s. Calculate the speed of light in air.
Solution:
Speed of yellow light in water (v) = 2.00 x 10⁸ m/s
Refractive Index of water with respect to air (μ) = 4/3
Refractive Index = Speed of yellow light in air / Speed of yellow light in water
Or, The speed of yellow light in air = Refractive Index × Speed of yellow light in water
or, = (4/3) × 2.00 x 10⁸ m/s
or, = 2.67 × 10⁸ m/s ≈ 3.0 × 10⁸ m/s
Hence, the required speed of yellow light in the air will be 3.0 × 10⁸ m/s.
