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2 years ago

There are seven fundamental quantities in physics. true or false

Physics

1 answer:

Gemiola [76]2 years ago

6 0

Answer:

True

Explanation:

mass, length, time, electric current, temperature, luminous intensity and amount of substance

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A motorcycle cop, parked at the side of a highway reading a magazine, is passed by a woman in a red Ferrari 308 GTS doing 120.0

jeyben [28]

Answer:

XZXDHF

Explanation:ZDHF

3 0

3 years ago

A fighter plane flying at constant speed 420 m/s and constant altitude 3300 m makes a turn of curvature radius 11000 m. On the g

Arada [10]

Answer:

"Apparent weight during the "plan's turn" is 519.4 N

Explanation:

The "plane’s altitude" is not so important, but the fact that it is constant tells us that the plane moves in a "horizontal plane" and its "normal acceleration" is $\mathrm{a}_{\mathrm{n}}=\frac{v^{2}}{R}$

Given that,

v = 420 m/s

R = 11000 m

Substitute the values in the above equation,

$a_{n}=\frac{420^{2}}{11000}$

$a_{n}=\frac{176400}{11000}$

$a_{n}=16.03 \mathrm{m} / \mathrm{s}^{2}$

It has a horizontal direction. Furthermore, constant speed implies zero tangential acceleration, hence vector a = vector a N. The "apparent weight" of the pilot adds his "true weight" "m" "vector" "g" and the "inertial force""-m" vector a due to plane’s acceleration, vector $W_{\mathrm{app}}=m(\text { vector } g \text { -vector a })$

In magnitude,

$| \text { vector } g-\text { vector } a |=\sqrt{\left(g^{2}+a^{2}\right)}$

$| \text { vector } \mathrm{g}-\text { vector } \mathrm{a} |=\sqrt{\left(9.8^{2}+16.03^{2}\right)}$

$| \text { vector } \mathrm{g}-\text { vector } \mathrm{a} |=\sqrt{(96.04+256.96)}$

$| \text { vector } \mathrm{g}-\text { vector } \mathrm{a} |=\sqrt{353}$

$| \text { vector } \mathrm{g}-\text { vector } \mathrm{a} |=18.78 \mathrm{m} / \mathrm{s}^{2}$

Because vector “a” is horizontal while vector g is vertical. Consequently, the pilot’s apparent weight is vector

$\mathrm{W}_{\mathrm{app}}=(18.78 \mathrm{m} / \mathrm{s}^ 2)(53 \mathrm{kg})=995.77 \mathrm{N}$

Which is quite heavier than his/her true weigh of 519.4 N

7 0

4 years ago

Read 2 more answers

Gold is used to make a super thin layer on the visors of astronauts' helmets because of which property in particular?

denis-greek [22]

Answer: C. good reflector of heat

Explanation:

In space, sunlight transfers heat by radiation to objects and bodies and this includes satellites and astronauts. In addition, although the peak of the sun's emission is in the visible region of the electromagnetic spectrum, a part is also emitted in infrared (transferring thermal energy or heat) and ultraviolet (especially in the upper part of the Earth's atmosphere).

That is why in space missions, objects and many satellites are covered by thin layers or sheets that reflect this thermal energy and thus avoid damaging the equipment due to high temperatures.

In this sense, among the reflective materials used are aluminum, silver, copper and gold; the latter being the most used because it does not corrode or oxidize (unlike silver and copper) and is more malleable than aluminum.

On the other hand, astronauts are also vulnerable to the effects of infrared radiation, especially their eyes, since the human eye has no receptors in the infrared spectrum. That is why the astronaut's helmet visor is covered with a thin layer of gold to avoid the dangerous effects of solar radiation.

4 0

4 years ago

Why can objects be made to float in a magnetic field?

dimulka [17.4K]

I would say that the answer is C

6 0

3 years ago

a quarterback throws a football with angle of elevation 40degrees and speed 60ft/s. Find the horizontal and vertical components

pshichka [43]

the horizontal velocity would be equal to
Vh = sin (40) /60
= 0.74 * 60
= 44

the Vertical velocity would be equal to
Vv = cos(40) * 60
=40

4 0

3 years ago

There are seven fundamental quantities in physics. true or false​

There are seven fundamental quantities in physics. true or false