What's the opposite of futility

Which one of the following is a derived SI unit?<br>A.newton B.meter C.mole d.Kilogram

marusya05 [52]

Answer:

Meter

Explanation:

I'd say meters, cause it's the SI unit of length,

which is a Derived Quantity.

5 0

3 years ago

The label has been scratched off a tuning fork and you need to know its frequency. From its size, you suspect that it is somewhe

bonufazy [111]

Answer:

255 Hz

Explanation:

With 5 beats per second with the 250 Hz fork, we know the unknown fork is either 250 - 5 = 245Hz or 250 + 5 = 255 Hz

With 15 beats per second with the 270 Hz fork, we know the unknown fork is either 270 - 15 = 255Hz or 270 + 15 = 285 Hz (most people would have a hard time discerning 15 beats per second... 5 per second is hard enough)

As 255 is the common frequency, it is the one selected.

3 0

3 years ago

If a circle was flattened by pushing down on it, it would most likely form into the shape of ----------- which has ----------- f

murzikaleks [220]

The question is looking for "ellipse" and "two" to fill in the blanks.

8 0

3 years ago

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Light travels through a liquid at 2.25e8 m/s. What is the index of refraction of the liquid?

Pavlova-9 [17]

Answer:

The index of refraction of the liquid is n = 1.33 equivalent to that of water

Explanation:

Solution:-

- The index of refraction of light in a medium ( n ) determines the degree of "bending" of light in that medium.

- The index of refraction is material property and proportional to density of the material.

- The denser the material the slower the light will move through associated with considerable diffraction angles.

- The lighter the material the faster the light pass through the material without being diffracted as much.

- So, in the other words index of refraction can be expressed as how fast or slow light passes through a medium.

- The reference of comparison of how fast or slow the light is the value of c = 3.0*10^8 m/s i.e speed of light in vacuum or also assumed to be the case for air.

- so we can mathematically express the index of refraction as a ratio of light speed in the material specified and speed of light.

- The light passes through a liquid with speed v = 2.25*10^8 m/s :

$n = c / v\\\\n = \frac{ 3*10^8 }{2.25*10^8} \\\\n = 1.33$

- The index of refraction of the liquid is n = 1.33 equivalent to that of water.

8 0

3 years ago

Read 2 more answers

The first artificial satellite to orbit the Earth was Sputnik I, launched October 4, 1957. The mass of Sputnik I was 83.5 kg, an

9966 [12]

Answer:

$-4.941*10^8J.$

Explanation:

To solve this exercise it is necessary to take into account the concepts related to gravitational potential energy, as well as the concept of perigee and apogee of a celestial body.

By conservation of energy we know that,

$\Delta U = \Delta_{perogee}-\Delta_{Apogee}$