Ask question

Ask question

All categories

3 years ago

11

Why has the model of the atom changed over time?

1 answer:

Makovka662 [10]3 years ago

7 0

<span>A.
The model of the atom evolved as scientists have made new discoveries.</span>

You might be interested in

An airplane with a speed of 92.3 m/s is climbing upward at an angle of 51.1 ° with respect to the horizontal. When the plane's a

devlian [24]

Answer:

a

$D = 1162.7 \ m$

b

$\beta =- 65.55^o$

Explanation:

From the question we are told that

The speed of the airplane is $u = 92.3 \ m/s$

The angle is $\theta = 51.1^o$

The altitude of the plane is $d = 532 \ m$

Generally the y-component of the airplanes velocity is

$u_y = v * sin (\theta )$

=> $u_y = 92.3 * sin ( 51.1 )$

=> $u_y = 71.83 \ m/s$

Generally the displacement traveled by the package in the vertical direction is

$d = (u_y)t + \frac{1}{2}(-g)t^2$

=> $-532 = 71.83 t + \frac{1}{2}(-9.8)t^2$

Here the negative sign for the distance show that the direction is along the negative y-axis

=> $4.9t^2 - 71.83t - 532 = 0$

Solving this using quadratic formula we obtain that

$t = 20.06 \ s$

Generally the x-component of the velocity is

$u_x = u * cos (\theta)$

=> $u_x = 92.3 * cos (51.1)$

=> $u_x = 57.96 \ m/s$

Generally the distance travel in the horizontal direction is

$D = u_x * t$

=> $D = 57.96 * 20.06$

=> $D = 1162.7 \ m$

Generally the angle of the velocity vector relative to the ground is mathematically represented as

$\beta = tan ^{-1}[\frac{v_y}{v_x } ]$

Here $v_y$ is the final velocity of the package along the vertical axis and this is mathematically represented as

$v_y = u_y - gt$

=> $v_y = 71.83 - 9.8 * 20.06$

=> $v_y = -130.05 \ m/s$

and v_x is the final velocity of the package which is equivalent to the initial velocity $u_x$

So

$\beta = tan ^{-1}[-130.05}{57.96 } ]$

$\beta =- 65.55^o$

The negative direction show that it is moving towards the south east direction

6 0

3 years ago

Meg walks 5 blocks south and then turns around and walks 8 blocks back to the north. The distance that she walks is 13 blocks. W

Drupady [299]

Three blocks north of where she started.

4 0

3 years ago

Polarizers #1 and #3 are "crossed" such that their transmission axes are perpendicular to each other. Polarizer #2 is placed bet

Tomtit [17]

Answer:

Explanation:

The angle between the polariser 1 and 2 is 60°

If I₁ be the intensity of light after polariser 1 , its intensity after polariser 2 that is I₂ can be expressed as follows

I₂ = I₁ cos² 60

= I₁ x 1/4

= I₁ x $\frac{1}{4}$

3 0

3 years ago

Leto [7]

One eighth of a gram will remain

3 0

3 years ago

After a while, the car started to go around a long bend, still maintaining its constant speed of 55 miles per hour. Is there a n

sukhopar [10]

Answer:

4) True. The change of direction needs an unbalanced force

Explanation:

Let us propose the resolution of the problem using Newton's second law.

F = m a

As the car is spinning the acceleration is centripetal

a = v2.r

F = m v2 / r

We can see that as the velocity of a vector even if its module does not change, the change of direction requires an external force.

Now we can analyze the statement if they are true or false

1) and 3) False, even when the speed changes, the direction changes

2) False with the speed change can be determined

4) True. The change of direction needs an unbalanced force

5) False are different things. the direction is where it is going and the speed is the magnitude of the vector

6 0

3 years ago