In 1911, Ernest Rutherford and his assistants Geiger and Marsden conducted an experiment in which they scattered alpha particles (nuclei of helium atoms) from thin sheets of gold. An alpha particle, having charge 2e and mass 6.64 10-27 kg, is a product of certain radioactive decays. The results of the experiment led Rutherford to the idea that most of an atom's mass is in a very small nucleus, with electrons in orbit around it. Assume an alpha particle, initially very far from a stationary gold nucleus, is fired with a velocity of 1.50 107 m/s directly toward the nucleus (charge 79e). What is the smallest distance between the alpha particle and the nucleus before the alpha particle reverses direction?

Answers

Answer 1
Answer:

Answer:

Explanation:

We shall apply conservation of mechanical energy

kinetic energy of alpha particle is converted into electric potential energy.

1/2 mv² = k q₁q₂/d , d is closest distance

d = 2kq₁q₂ / mv²

= 2 x 9 x 10⁹ x 79e x 2e / 4mv²

= 1422 x2x (1.6 x 10⁻¹⁹)² x 10⁹ /4x 1.67 x 10⁻²⁷ x (1.5 x 10⁷)²

= 3640.32 x 10⁻²⁹ /2x 3.7575 x 10⁻¹³

= 484.4 x 10⁻¹⁶

=48.4  x 10⁻¹⁵ m


Related Questions

I need help with the following three physics problems please!
If the absolute temperature of a gas is 600 K, the temperature in degrees Celsius isa. 273°C.c. 705°C.b. 327°C.d. 873°C.
Little is known about much of earth’s early history because ____. a. precambrian rocks have been deeply buried b. precambrian rocks have been changed by heat and pressure c. precambrian soft-bodied life-forms weren’t often preserved as fossils d. all of the above
Two point charges are separated by 6 cm. The attractive force between them is 20 N. Find the force between them when they are separated by 12 cm. (Why can you solve this problem without knowing the magnitudes of the charges
Modern fireplaces use a ____ to burn exhaust gases. boiler furnace radiator catalytic combustor

What sort of process converts the mechanized energy in the ocean into electricity?

Answers

I think it is the wave energy. 
Wave energy also known as the ocean energy is the energy harnessed from the ocean or sea waves. It is a source of power that comes from the endless march of the waves as they roll into the shore then back out. Using wave energy is advantageous as they are environmental friendly as there are no harmful byproducts, and also the energy from waves can be taken directly into electricity-producing machinery and used to power generators. 

Money is useful to people because it is __________.Select one of the options below as your answer:a. a medium of exchange
b. prestigious
c. nice to look at
d. something that makes you feel good

Answers

a. A medium of exchange ....Hope am right !!!
The answer is A because money is a form of barter in a sense.

How is balanced force applied to the egg drop project?

Answers

Answer:

It is the gravity of the angles that connect with the egg and the angles of it

Must be 8 letters (Dimensional Analysis escape room)

Answers

Answer: A-B-C-E-G-K-H-I

Explanation:

Ok, we start at A.

16 pints = x gallons.

We know that:

1 pint = 0.125 al

then:

16pint = 16*(0.125gal) = 2 gal.

The second letter is B.

Now we have:

12,320 yd = X mi

And we know that:

1 mi = 1760 yd.

Then 12,320yd = (12,320/1760) mi = 7mi

the letter is C.

Now we have:

432 cups = X gals

and:

1 cup = 0.0625 gal

then 432 cups = 432*(0.0625 gal) = 27 gal.

The next letter is E.

Now we have:

1/4 ton = X pounds.

And 1 ton = 2000 pounds

then 1/4 ton = (1/4)*2000 pounds = 500 pounds

The next letter is G.

Now we have:

3.5 gal = X ounces.

and we know that:

1 gal = 128 oz

Then:

3.5 gal = 3.5*(128oz) = 448oz

The next letter is K.

Now we have:

1/2 day = x minutes.

and we know that:

1 day = 24*60 min = 1440 min

then 1/2 day = (1/2)*1440 min = 720 min.

The next letter is H.

Now we have:

360 in = x yd

And we know that:

1yd = 36 inches.

then 360 in = (360/36) = 10 yd.

The next letter is I

Now we have:

56 cups = x quarts.

and we know that;

1cup = 0.25 quart

then: 56 cups = 56*0.25 quart = 14

So here this ends.

Then the code is:

A-B-C-E-G-K-H-I

If we decrease the distance an object moves we will

Answers

... without changing the speed of the object, then
we will not have to wait so long for the object to get
where it is going.
If we decrease the distance an object moves, we will decrease the amount of work done.

A motorist is driving at 20m/s when she sees that a traffic light 200m ahead has just turned red. She knows that this light stays red for 15s, and she wants to reach the light just as it turns green again. It takes her 1.0s to step on the brakes and begin slowing. What is her speed as she reaches the light at the instant it turns green?

Answers

Answer:

8.57 m/s

Explanation:

let's list out available parameters:

Initial velocity, u = 20 m/s

Time = 15 - 1 = 14 s

Distance, s = 200 m

Final velocity = ?

We are assuming a uniformly accelerated motion.

Using one of the equations of motion s = \left((u+v)/(2)\right)t

v = (2s)/(t)-u

v=(2*200)/(14)-20

v=28.6 - 20

v=8.6 m/s

Final answer:

To stop just as the light turns green, the motorist needs to decelerate in a controlled manner. The effective time to cover the distance after seeing the red light is 14 seconds, disregarding the 1 second it takes to react and press the brakes. Therefore, as she reaches the traffic signal when it turns green, her speed is 0 m/s.

Explanation:

This situation can be approached using the concept of kinematics in Physics. To solve it, we need to consider total time and total distance traveled. The motorist is driving towards the traffic light, which is 200m away, and the light stays green for 15 seconds. However, since it takes her 1 second to step on the brakes, effectively, she has 14 seconds to travel to the light.

Since she starts braking the car, she begins to decelerate. While decelerating, time is the only determinant of the distance covered, not the speed. As she reaches the light, the speed would be zero regardless of the initial speed or distance if the deceleration is constant. So, when the light turns green, her speed will be 0 m/s.

Learn more about Deceleration here:

brainly.com/question/32899180

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