I'm bored. ........................

7th grade science i mark as brainliest

andrey2020 [161]

Answer:

YOU ARE NOOB BECAUSE YOU ARE FREE FIRE PLAYER

6 0

2 years ago

Explain how do single fixed and single movable Pulley make our work easier

ikadub [295]

The force is in the same direction as the load moves. The force is up and the load moves up. This is the same results without the pulley. A fixed pulley makes work easier because you can pull down instead of pushing something up.

8 0

2 years ago

Which of the following statements are true regarding electromagnetic waves traveling through a vacuum? (Select all that apply.)

Ber [7]

Correct choices:

- All waves travel at 3.00 108 m/s.

- The electric and magnetic fields associated with the waves are perpendicular to each other and to the direction of wave propagation.

Explanation:

Let's analyze each statement:

- All waves have the same wavelength. --> FALSE. Electromagnetic waves have a wide range of wavelengths, from less than 10 picometers (gamma rays) to hundreds of kilometers (radio waves)

- All waves have the same frequency. --> FALSE. As for the wavelength, electromagnetic waves have a wide range of frequencies also.

- All waves travel at 3.00 108 m/s. --> TRUE. This value is called speed of light, and it is one of the fundamental constant: it is the value of the speed of all electromagnetic waves in a vacuum.

- The electric and magnetic fields associated with the waves are perpendicular to each other and to the direction of wave propagation. --> TRUE. Electromagnetic waves are transverse waves, which means that their oscillations (represented by the electric field and the magnetic field) occurs perpendicularly to the direction of motion of the wave.

- The speed of the waves depends on their frequency. --> FALSE. In a vacuum, the speed of ALL electromagnetic waves is always equal to c, regardless of the frequency.

4 0

3 years ago

Read 2 more answers

A paper airplane is thrown westward at a rate of 6 m/s. The wind is blowing at 8 m/s towards the north. Which of the following d

Andrew [12]

since airplane is thrown towards west with speed 6 m/s

while air is blowing with speed 8 m/s towards north

so here the net speed of air plane will be the resultant of airplane speed and wind speed always

SO here we can say it would be a combination of vector along west with must be of length 6 m/s and other vector is towards north with is of length 8 m/s

so correct answer must be 1st option

5 0

3 years ago

The magnitude of the gravitational field strength near Earth's surface is represented by

Zanzabum

Answer:

The magnitude of the gravitational field strength near Earth's surface is represented by approximately $9.82\,\frac{m}{s^{2}}$ .

Explanation:

Let be M and m the masses of the planet and a person standing on the surface of the planet, so that M >> m. The attraction force between the planet and the person is represented by the Newton's Law of Gravitation:

$F = G\cdot \frac{M\cdot m}{r^{2}}$

Where:

$M$ - Mass of the planet Earth, measured in kilograms.

$m$ - Mass of the person, measured in kilograms.

$r$ - Radius of the Earth, measured in meters.

$G$ - Gravitational constant, measured in $\frac{m^{3}}{kg\cdot s^{2}}$ .

But also, the magnitude of the gravitational field is given by the definition of weight, that is:

$F = m \cdot g$

Where:

$m$ - Mass of the person, measured in kilograms.

$g$ - Gravity constant, measured in meters per square second.

After comparing this expression with the first one, the following equivalence is found:

$g = \frac{G\cdot M}{r^{2}}$

Given that $G = 6.674\times 10^{-11}\,\frac{m^{3}}{kg\cdot s^{2}}$ , $M = 5.972 \times 10^{24}\,kg$ and $r = 6.371 \times 10^{6}\,m$ , the magnitude of the gravitational field near Earth's surface is:

$g = \frac{\left(6.674\times 10^{-11}\,\frac{m^{3}}{kg\cdot s^{2}} \right)\cdot (5.972\times 10^{24}\,kg)}{(6.371\times 10^{6}\,m)^{2}}$

$g \approx 9.82\,\frac{m}{s^{2}}$

The magnitude of the gravitational field strength near Earth's surface is represented by approximately $9.82\,\frac{m}{s^{2}}$ .

4 0

3 years ago