All categories

2 years ago

Establish the relation between current density and electron drift velocity?

1 answer:

7 0

Answer:the drift velocity is directly proportional to current. The drift velocity is the average velocity that a particle, such as an electron, attains in a material due to an electric field. In general, an electron will propagate randomly in a conductor at the Fermi velocity.Mar 11, 2017

You might be interested in

Which choice correctly describes what happens during heating?

Masja [62]

Answer:

Option 4

Explanation:

During heating actually heat transfer takes place from a body at higher temperature to a body at lower temperature and the heat transfer takes place until both attain the same temperature

Therefore heat transfer depends on the temperature of the systems

Now while comparing the thermal energies of the systems, if both the systems have same mass then the system which is at higher temperature has greater thermal energy when compared to the system which is at lower temperature

So in this case assuming that both the systems have same mass then the energy will leave the system with greater thermal energy and go into the system with less thermal energy as the system with greater thermal energy in this case will be at higher temperature and we are considering this assumption because thermal energy not only depends on temperature but also depends on mass of the system

7 0

3 years ago

David is driving a steady 30 m/s when he passes Tina, who is sitting in her car at rest. Tina begins to accelerate at a steady 2

dangina [55]

A. 441 m B: 46.0 m/s

5 0

2 years ago

A ball is hit with a paddle, causing it to travel straight upward. It takes 2.90 s for the ball to reach its maximum height afte

zmey [24]

Answer:

A. 28.42 m/s

B. 41.21 m

Explanation:

From the question given above, the following data were obtained:

Time (t) to reach the maximum height = 2.90 s

Initial velocity (u) =?

Maximum height (h) =?

A. Determination of the initial velocity of the ball.

Time (t) to reach the maximum height = 2.90 s

Final velocity (v) = 0 m/s (at maximum height)

Acceleration due to gravity (g) = 9.8 m/s²

Initial velocity (u) =?

v = u – gt (since the ball is going against gravity)

0 = u – (9.8 × 2.9)

0 = u – 28.42

Collect like terms

0 + 28.42 = u

u = 28.42 m/s

Thus, the initial velocity of the ball is 28.42 m/s

B. Determination of the maximum height reached by the ball.

Final velocity (v) = 0 m/s (at maximum height)

Acceleration due to gravity (g) = 9.8 m/s²

Initial velocity (u) = 28.42 m/s

Maximum height (h) =?

v² = u² – 2gh (since the ball is going against gravity)

0² = 28.42² – (2 × 9.8 × h)

0 = 807.6964 – 19.6h

Collect like terms

0 – 807.6964 = – 19.6h

– 807.6964 = – 19.6h

Divide both side by – 19.6

h = – 807.6964 / – 19.6

h = 41.21 m

Thus, the maximum height reached by the ball is 41.21 m

5 0

3 years ago

Understand that the acceleration vector is in the direction of the change of the velocity vector. In one dimensional (straight l

MaRussiya [10]

Answer:

a = √ (a_t² + a_c²)

a_t = dv / dt , a_c = v² / r

Explanation:

In a two-dimensional movement, the acceleration can have two components, one in each axis of the movement, so the acceleration can be written as the components of the acceleration in each axis.

a = aₓ i ^ + a_y j ^

Another very common way of expressing acceleration is by creating a reference system with a parallel axis and a perpendicular axis. The axis called parallel is in the radial direction and the perpendicular axis is perpendicular to the movement, therefore the acceleration remains

a = √ (a_t² + a_c²)

where the tangential acceleration is

a_t = dv / dt

the centripetal acceleration is

a_c = v² / r

8 0

3 years ago

An ambulance emits a frequency of 450 Hz from its siren. What frequency is heard by a man as the ambulance moves toward him? les

Zepler [3.9K]

Frequency is defined as the number of repetitions of waves occurring in 1 second. The frequency heard by the man as the ambulance move toward him will be greater than 450 Hz.

<h3>What is the frequency ?</h3>

Frequency is defined as the number of cycles completed in 1 second. Frequency is given by the formula as,

$\rm{Frequency =\frac{1}{time } }$

As the formula shows frequency is inversely proportional to the time that shows if the time is decreasing frequency will increase and vice versa.

In the above case, the ambulance is moving toward the men. So that the time to meet up is decreased that's why the frequency will be greater than the initial frequency from the siren.

Hence the frequency heard by the man as the ambulance move toward him will be greater than 450 Hz.

To learn more about frequency refer to the link ;

brainly.com/question/4393505

3 0

2 years ago