Question

Water flows over a section of Niagara Falls at a rate of 1.31 × 106 kg/s and falls 71 m. The acceleration of gravity is 9.8 m/s 2 . How many 40 W bulbs can be lit with this power?

Answer 1

2×10⁷ bulbs.

Step-by-step explanation:

From the question,

The the power generated by the water flows over a Niagara section is given as,

P = M'gh......................... Equation 1

Where M' = Fall rate, g = acceleration due to gravity, h = height of fall.

Given: M' = 1.31×10⁶ kg/s, g = 9.8 m/s², h = 71 m

Substitute into equation 1

P = 1.31×10⁶×9.8×71

P = 9.115×10⁸ W.

Number of 40 W bulb it can lit = P/40

= 9.115×10⁸/40 = 2.27×10⁷ ≈ 2×10⁷ bulbs.