contestada

The hour, minute, and second hands on a clock are 0.25 m , 0.31 m , and 0.34 m long, respectively.
What are the distances traveled by the tips of the hands in a 40 min interval?
Express your answers using two significant figures separated by commas.

Respuesta :

In 1 hour, the hour hand sweeps across 1/12 of the clock's face. In 40 min, the hour hand travels (40 min)/(60 min) = 2/3 of the path it covers in an hour, so a total of 1/12 × 2/3 = 1/18 of the clock's face. This hand traces out a circle with radius 0.25 m, so in 40 min its tip traces out 1/18 of this circle's radius, or

1/18 × 2π (0.25 m) ≈ 0.087 m

The minute hand traverses (40 min)/(60 min) = 2/3 of the clock's face, so it traces out 2/3 of the circumference of a circle with radius 0.31 m:

2/3 × 2π (0.31 m) ≈ 1.3 m

The second hand completes 1 revolution each minute, so in 40 min it would fully trace the circumference of a circle with radius 0.34 m a total of 40 times, so it covers a distance of

40 × 2π (0.34 m) ≈ 85 m

The distances traveled by the tips of the hour hand, minute hand and second hand in a 40-min interval are 0.087 m, 1.3 m and 85 m respectively.

What are the hands of a clock?

In a clock, there are three hands of the clock. One is hour hand, second is minute hand and third one is second hand.

The hour hand of the clock is 0.25 m long. The hour hand sweep 1/12 of the clock face each hour (as there are 12 hours in a clock). Thus, in a 40-minute interval, it will travel the distance of,

[tex]d=2\pi\times\dfrac{40}{12\times60}(0.25)\\d\approx0.087\rm\; m[/tex]

The minute hand of the clock is 0.25 m long. In a 40-minute interval, it will travel the distance of,

[tex]d=2\pi\times\dfrac{40}{60}(0.31)\\d\approx1.3\rm\; m[/tex]

The second hand of the clock is 0.25 m long. In a 40-minute interval, it will travel the distance of,

[tex]d=2\pi\times\dfrac{40\times60}{60}(0.34)\\d\approx85\rm\; m[/tex]

Thus, the distances traveled by the tips of the hour hand, minute hand and second hand in a 40 min interval are 0.087 m, 1.3 m and 85 m respectively

Learn more about the hands of a clock here;

https://brainly.com/question/1138016

.