At what speed the velocity head at a stream of water be equal to 40 cm?
Correct answer: A. 282.8 cm/sec
- A. 282.8 cm/sec
- B. 432.6 cm/sec
- C. 632.6 cm/sec
- D. 832.6 cm/sec
Explanation
To find the speed at which the velocity head equals 40 cm, use the formula for velocity head: v²/2g = h, where v is the speed, g is the acceleration due to gravity (980 cm/sec²), and h is the height (40 cm). Solving for v gives v = sqrt(2gh). Substituting the known values, v = sqrt(2 * 980 * 40) = 282.8 cm/sec. Therefore, Option A is correct. The other options provide speeds that are not consistent with the given velocity head of 40 cm.
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