1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
11Alexandr11 [23.1K]
3 years ago
11

A color television tube generates some X-rays when its electron beam strikes the screen. What is the shortest wavelength of thes

e X-rays, in meters, if a 31 kV potential is used to accelerate the electrons? (Note that TVs have shielding to prevent these X-rays from reaching viewers.)
Physics
1 answer:
Margaret [11]3 years ago
5 0

Answer:  4.0024 x 10^ -11 m or 0.040024 nm

Explanation:

λ = h c/ΔE

λ = wave lenght

h = 6.626 x 10 ^ -34  m² kg /s  = planck constant

ΔE = 31 keV potential ( 1 keV = 1.6021 x 10^-16J)

c = velocity of light = 3 x 10⁸ m/s

substitute gives

λ  =    <u>6.626 x 10 ^ -34  m² kg /s x 3 x 10⁸ m/s</u>  = 4.0024 x 10^ -11 m

                 31 x 1.6021x10^-16 J

You might be interested in
3. Maverick and Goose are flying a training mission in their F-14. They are
Elanso [62]

Answer:

A. The bomb will take <em>17.5 seconds </em>to hit the ground

B. The bomb will land <em>12040 meters </em>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}}

Since we have y_0=1500m

t=\sqrt{\frac{2(1500)}{9.8}}

t=17.5 sec

Replacing in [2]

x = 688\ m/sec \ (17.5sec)

x = 12040\ m

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

6 0
3 years ago
An aluminum cup contains 225 g of water and a 40 g copper stirrer, all at 27°C. A 410 g sample of silver at an initial temperatu
fomenos

Answer:

130.22 g

Explanation:

Parameters given:

Mass of water Mw = 225 g

Mass of stirrer Ms = 40 g

Mass of silver M(S) = 410 g

By applying the law of conservation of energy:

(McCc + MsCs + MwCw)ΔTw = M(S)C(S)ΔT(S)

where Mc = Mass of cup

Cc = Specific heat capacity of aluminium cup = 900 J/gC

Cs = Specific heat capacity of copper stirrer = 387 J/gC

Cw = Specific heat capacity of water = 4186 J/gC

ΔTw = change in temperature of water = 32 - 27 = 5 °C

C(S) = Specific heat capacity of silver = 234 J/gC

ΔT(S) = change in temperature of silver = 88 - 32 = 56 °C

Therefore:

[(Mc * 900) + (40 * 387) + (225 * 4186)] * 5 = 410 * 234 * 56

(900Mc + 957330) * 5 = 5276700

900Mc + 957330 = 5276700 / 5 = 1074528

900Mc = 1074528 - 957330

900Mc = 117198

Mc = 117198/ 900

Mc = 130.22 g

The mass of the cup is 130.22 g.

5 0
3 years ago
Julie throws a ball to her friend Sarah. The ball leaves Julie's hand a distance 1.5 meters above the ground with an initial spe
iris [78.8K]

Answer:

Explanation:

1.  V_{x} = V_{0} * cos\alpha ⇒ 16*cos32 ≈ 13.6 m/s (13.56)

2. V_{y} = V_{0} * sin\alpha ⇒ 16* sin32 ≈ 9.4 m/s

3. y_{max} = \frac{v_{0}^2*sin^2\alpha}{2g}= \frac{16^2*sin^232}{2*9.8} (the g (gravity) depends on the country but i'll take the average g which is 9.2m/s^2)

y_{max} ≈ 3.6677+1.5 ≈ 5.2m

4.  x_{max} = \frac{v_{0}^2*sin(2\alpha)}{g}=\frac{16^2*sin(2*32)}{9.8} ≈ 23.5m (23.47)

5. -

answer 4 could be wrong, not certain about that one and i don't know 5

3 0
3 years ago
For elliptical obits: the direction of the velocity of the satellite is _______________________ (always, seldom, never) perpendi
alexandr1967 [171]

Answer:

For elliptical orbits: seldom

For circular orbits: always

Explanation:

We start by analzying a circular orbit.

For an object moving in circular orbit, the direction of the acceleration (centripetal acceleration) is always perpendicular to the direction of motion of the object.

Since acceleration has the same direction of the force (according to Newton's second law of motion), this means that the direction of the force (the centripetal force) is always perpendicular to the velocity of the object.

So for a circular orbit,

the direction of the velocity of the satellite is always perpendicular to the net force acting upon the satellite.

Now we analyze an elliptical orbit.

An elliptical orbit correponds to a circular orbit "stretched". This means that there are only 4 points along the orbit in which the acceleration (and therefore, the net force) is perpendicular to the direction of motion (and so, to the velocity) of the satellite. These points are the 4 points corresponding to the intersections between the axes of the ellipse and the orbit itself.

Therefore, for an elliptical orbit,

the direction of the velocity of the satellite is seldom perpendicular to the net force acting upon the satellite.

7 0
3 years ago
Plz i need to knowwwwwwwwwew asap
mario62 [17]
I can’t see it’s too blurry
6 0
3 years ago
Other questions:
  • ¿Existe relación entre la rapidez para realizar trabajo y la velocidad del cuerpo?
    10·1 answer
  • Why is water always used in energy generation (water -&gt; steam -&gt; turbine) instead of a liquid with a lower specific heat c
    9·1 answer
  • A horizontal sheet of negative charge has a uniform electric field E = 3000N/C. Calculate the electric potential at a point 0.7m
    9·1 answer
  • What is the mass of an object with a momentum of 250 kgm/s and a velocity of 5 m/s?
    8·2 answers
  • A block of mass m sits at rest on a rough inclined ramp that makes an angle θ with the horizontal. What must be true about force
    10·1 answer
  • Estimate the number of atoms in 1 cm^3 of a solid
    15·1 answer
  • The rate at which an object move is it's
    9·1 answer
  • 3. A large crane lifts a 25,000 kg mass in the air. The amount of work that must be done by the
    8·1 answer
  • How can we represent a narrow beam of light?
    15·2 answers
  • an object is acted on by a drag force with a magnitude that is proportional to the speed. the object accelerates downward at 3.0
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!