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
Eddi Din [679]
3 years ago
6

Which is something that a vacuum tube cannot do?

Physics
2 answers:
Oxana [17]3 years ago
8 0
D) concert electrical energy into thermal energy
Butoxors [25]3 years ago
4 0

Answer:

D

Explanation:

A vacuum tube is a glass tube that creates the conditions of a vacuum to allow for electric current to pass through it.

Originally, vacuum tubes were used in electronics to amplify electric signals, however, today they have been replaced by more efficient systems, such as transistors.

A vacuum tube can change alternating current into direct current, it can turn a current on or off, and as stated above, it can increase the signal strength. However, it cannot change electrical energy into thermal energy, and that is why the answer is D.

You might be interested in
The froghopper, Philaenus spumarius, holds the world record for insect jumps. When leaping at an angle of 58.0 above the horizon
kirza4 [7]

Answer:

A) 3.79 m/s  B) 1.33 m

Explanation:

A)

  • Horizontal movement:
  • Once in the air, no forces act on the froghopper, so it keeps moving with the same initial horizontal speed.
  • This horizontal component, is the projection of the velocity vector on the horizontal direction (x-axis):

        v_{ox} = v_{o} *cos (58.0 deg)

  • The horizontal displacement can be simply calculated as follows:

        x = v_{ox} *t

  • Vertical movement:
  • As the vertical and horizontal are independent each other (due to they are perpendicular, so there is no projection of one movement on the other), in the vertical direction, all happens as if would be a body thrown upward with a given initial vertical velocity.
  • This velocity can be found as the projection of the velocity vector on the vertical direction (y-axis):

        v_{oy} = v_{o} *sin (58.0 deg) (1)

  • Once in the air, the gravity will cause that the froghopper be slow down, till it reaches to the maximum height, where it will come momentarily to an stop.
  • In that moment, we can apply the following kinematic equation:

        v_{fy} ^{2} -v_{oy} ^{2} = 2*g*h_{max}

  • where vfy = 0, g = -9.8m/s2, hmax = 52.7 cm= 0.527 m
  • Replacing by the givens, we can solve for voy:

        v_{oy} =\sqrt{2*g*h_{max}} = \sqrt{2*9.8m/s2*0.527m} =3.21 m/s

  • From the equation (1), we can solve for the magnitude of the initial velocity, v₀:

        v_{o} = \frac{v_{oy}}{sin 58.0} =\frac{3.21m/s}{0.848} = 3.79 m/s

B)

  • With the value of the magnitude of the initial velocity, we can find the horizontal component vox, as follows:

        v_{ox} = v_{o} *cos (58.0 deg) =\\  \\ 3.79 m/s * cos (58.0deg) = 2.01 m/s

  • In order to know the horizontal distance travelled, we need to find the time that the insect was in the air.
  • We can use the equation for the vertical displacement, replacing this value by 0, as follows:

       y = 0 = v_{oy} *t -\frac{1}{2} * g *t^{2}

  • Replacing by  the givens, and rearranging terms, we can solve for t:

        t_{air} =\frac{2*v_{oy} }{g} = \frac{2*3.21 m/s}{9.8 m/s} = 0.66 s

  • Finally, we find the horizontal displacement, as follows:

       x_{max}  = v_{ox} *t_{air} = 2.01 m/s * 0.66 s \\ \\ x_{max} = 1.33 m

  • The horizontal distance covered by  the froghopper was 1.33 m.
4 0
3 years ago
PLEASE HELP ASAP!!! CORRECT ANSWER ONLY PLEASE!!!
guajiro [1.7K]

A wave with a greater amplitude carries more energy to wherever it goes.

3 0
3 years ago
Read 2 more answers
How do you calculate the electric force by object a exerted on object a (itself)?
max2010maxim [7]

I don't think an object can exert a force on itself.

Try it: Get up on a skateboard, and see if you can do anything to yourself that makes you start moving ... without touching anything else.

It'll be easy to tell if you succeed. If you actually do exert an unbalanced force on yourself, then you'll begin to accelerate.

5 0
3 years ago
A circuit has a voltage drop of 24.0 V across a 30.0 resistor that carries a
beks73 [17]

(A) 19.2 W

<u>Explanation:</u>

Given-

Voltage drop, V = 24 V

Resistor = 30Ω

Current, I = 0.8 A

Power, P = ?

We know,

P = VI

P = 24 (0.8)

P = 19.2 W

Therefore, the power conducted by the resistor is 19.2 W

6 0
3 years ago
Read 2 more answers
Can someone please explain number 8?
guajiro [1.7K]

Answer: Ax=(Vx-Vox)/(T)

Vx=Vox+Ax*T

Solving for Ax in terms of Vx, Vox, T

Vx-Vox=Ax*t

Ax=(Vx-Vox)/(T)

This is saying the acceleration in the x-direction can be found by taking the difference between the finial and initial Velocity in x-direction and dividing it by the Total Time.

Any questions please feel free to ask. Thanks

8 0
3 years ago
Other questions:
  • The drawing shows a side view of a swimming pool. The pressure at the surface of the water is atmospheric pressure. The pressure
    7·2 answers
  • The work done on a 10 kilogram mass to give it a speed of 5 meters per second is
    8·1 answer
  • Energy from the sun is _energy
    14·2 answers
  • T or F science is a continually evolving discipline
    15·2 answers
  • Which gas prevents damaging ultraviolet radiation from the sun from reaching earth's surface?
    10·2 answers
  • What is the power of 10 when 157,821 is written in scientific notation?
    11·2 answers
  • People have proposed driving motors with the earth's magnetic field. This is possible in principle, but the small field means th
    8·1 answer
  • A house is advertised as having 1460 square feet under roof. What is the area of this house in square meters?
    14·2 answers
  • A 3.2 kg ball that is moving straight upward has 17 Joules of kinetic energy. The total mechanical energy is 25 Joules.
    7·1 answer
  • Could someone please help
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!