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In this activity, you will research how scientists developed historical

Darya [45]

Answer: Bohr's model (1913)

Niels Bohr improved Rutherford's model. Using mathematical ideas, he showed that electrons occupy shells or energy levels around the nucleus. The Dalton model has changed over time because of the discovery of subatomic particles.

Bohr's model (1913)

Niels Bohr improved Rutherford's model. Using mathematical ideas, he showed that electrons occupy shells or energy levels around the nucleus. The Dalton model has changed over time because of the discovery of subatomic particles

Dalton's atomic theory proposed that all matter was composed of atoms, indivisible and indestructible building blocks. While all atoms of an element were identical, different elements had atoms of differing size and mass.

John Dalton

The idea that everything is made of atoms was pioneered by John Dalton (1766-1844) in a book he published in 1808. He is sometimes called the "father" of atomic theory, but judging from this photo on the right "grandfather" might be a better term.

Explanation:

8 0

2 years ago

An airplane starts from A and flies to B at a constant speed. After reaching B it returns to A at the same speed. There was no w

Dafna1 [17]

Answer:

When there is wind it takes longer

Explanation:

With no wind, the round trip time is

$t_1=\frac{d}{v}+\frac{d}{v}=\frac{2d}{v}$

When we have a constant wind speed w

$t_2=\frac{d}{v-w} +\frac{d}{v+w} =\frac{2vd}{v^{2} -w^{2}}$

comparing the reciprocal times;

$\frac{1}{t_2}=\frac{v^{2}-w^{2} }{2vd}=\frac{v}{2d}-\frac{w^{2}}{2vd} \leq \frac{v}{2d}=\frac{1}{t_1}$

This means that t1 is smaller than t2, ergo, it takes longer with wind

4 0

2 years ago

If the same pressure is exerted over a greater area will more of less force result? Group of answer choices :

Zigmanuir [339]

Answer:

More force

Explanation:

Pressure and force are related by the equation:

$p=\frac{F}{A}$

where

p is the pressure

F is the force

A is the area

We can re-arrange the equation as

$F=pA$

In this problem, the pressure is kept the same (p' = p) while the area is increased. As we can see from the previous equation, the force applied is directly proportional to the area: therefore, a greater area means also a greater force.

8 0

3 years ago

3. Maverick and Goose are flying a training mission in their F-14. They are

Elanso [62]

Answer:

A. The bomb will take 17.5 seconds to hit the ground

B. The bomb will land 12040 meters on the ground ahead from where they released it

Explanation:

Maverick and Goose are flying at an initial height of $y_0=1500m$ , and their speed is v=688 m/s

When they release the bomb, it will initially have the same height and speed as the plane. Then it will describe a free fall horizontal movement

The equation for the height y with respect to ground in a horizontal movement (no friction) is

$y=y_0 - \frac{gt^2}{2}$ [1]

With g equal to the acceleration of gravity of our planet and t the time measured with respect to the moment the bomb was released

The height will be zero when the bomb lands on ground, so if we set y=0 we can find the flight time

The range (horizontal displacement) of the bomb x is

$x = v.t$ [2]

Since the bomb won't have any friction, its horizontal component of the speed won't change. We need to find t from the equation [1] and replace it in equation [2]:

Setting y=0 and isolating t we get

$t=\sqrt{\frac{2y_0}{g}}$