Ask question

Ask question

All categories

2 years ago

14

A Circular loop in the plane of a paper lies in a 0.65 TT magnetic field pointing into the paper. The loop's diameter changes fr

om 17.5 cmcm to 6.6 cmcm in 0.48 ss .
a) Determine the direction of the induced current and justify your answer.b) Determine the magnitude of the average induced emf.c) If the coil resistance is 2.5 Ω, what is the average induced current?

1 answer:

Kobotan [32]2 years ago

6 0

Answer:

Explanation:

magnetic filed, B = 0.65 T

initial diameter, d = 17.5 cm

final diameter, d' = 6.6 cm

time, t = 0.48 s

(a) According to Lenz's law, the direction of induced current is clockwise.

(b) Let e is the induced emf.

initial area, A = π r² = 3.14 x 0.0875 x 0.0875 = 0.024 m²

final area, A' = π r'² = 3.14 x 0.033 x 0.033 = 0.00342 m²

change in area, ΔA = A - A' = 0.024 - 0.00342 = 0.02058 m²

The magnitude of induced emf is given by

$e=\frac{d\phi }{dt}$

$e=B\frac{\Delta A }{dt}$

e = 0.65 x 0.02058 / 0.48

e = 0.028 V

(c) R = 2.5 ohm

i = e / R

i = 0.028 / 2.5

i = 0.011 A

You might be interested in

you slide abox of books at constant speed up a30 degree ramp, applying a force of 200 newtons directed up the slope. The coeffic

Tomtit [17]

The work done is 400 J

Explanation:

The work done by you in pushing the box along the slope is given by

$W=Fd$

where

F is the magnitude of the force applied

d is the distance covered by the box along the slope

Here we have the following:

F = 200 N is the magnitude of the force applied

$d=\frac{h}{sin \theta}$ is the distance covered, where

h = 1 m is the vertical rise

$\theta=30^{\circ}$ is the slope of the plane

Substituting and solving, we find

$W=F\frac{h}{sin \theta}=\frac{(200)(1)}{sin 30^{\circ}}=400 J$

Learn more about work:

brainly.com/question/6763771

brainly.com/question/6443626

#LearnwithBrainly

5 0

2 years ago

What are the components of the "Earth Radiation Budget?"

Alex777 [14]

Answer:

The energy entering, reflecting, absorbed, and emitted by the earth system are the components of the Earth's radiation budget.

Explanation:

I hope this helps also I hope you have a great day and a new year.

4 0

2 years ago

FIGURE 2 shows a 1.5 kg block is hung by a light string which is wound around a smooth pulley of radius 20 cm. The moment of ine

Sindrei [870]

Answer:

At t = 4.2 s

Angular velocity: 6. 17 rad /s

The number of revolutions: 2.06

Explanation:

First, we consider all the forces acting on the pulley.

There is only one force acting on the pulley, and that is due to the 1.5 kg mass attached to it.

Therefore, the torque on the pulley is

$\tau=Fd=mg\cdot R$

where m is the mass of the block, g is the acceleration due to gravity, and R is the radius of the pulley.

Now we also know that the torque is related to angular acceleration α by

$\tau=I\alpha$

therefore, equating this to the above equation gives

$mg\cdot R=I\alpha$

solving for alpha gives

$\alpha=\frac{mgR}{I}$

Now putting in m = 1.5 kg, g = 9.8 m/s^2, R = 20 cm = 0.20 m, and I = 2 kg m^2 gives

$\alpha=\frac{1.5\cdot9.8\cdot0.20}{2}$ $\boxed{\alpha=1.47s^{-2}}$

Now that we have the value of the angular acceleration in hand, we can use the kinematics equations for the rotational motion to find the angular velocity and the number of revolutions at t = 4.2 s.

The first kinematic equation we use is

$\theta=\theta_0+\omega_0t+\frac{1}{2}\alpha t^2$

since the pulley starts from rest ω0 = 0 and theta = 0; therefore, we have

$\theta=\frac{1}{2}\alpha t^2$

Therefore, ar t = 4.2 s, the above gives

$\theta=\frac{1}{2}(1.47)(4.2)^2$

$\boxed{\theta=12.97}$

So how many revolutions is this?

To find out we just divide by 2 pi:

$\#\text{rev}=\frac{\theta}{2\pi}=\frac{12.97}{2\pi}$ $\boxed{\#\text{rev}=2.06}$

Or about 2 revolutions.

Now to find the angular velocity at t = 4.2 s, we use another rotational kinematics equation:

$\omega^2=w^2_0+2\alpha(\Delta\theta)_{}$

Since the pulley starts from rest, ω0 = 0. The change in angle Δθ we calculated above is 12.97. The value of alpha we already know to be 1.47; therefore, the above becomes:

$\omega^2=0+2(1.47)(12.97)$ $w^2=38.12$ $\boxed{\omega=6.17.}$

Hence, the angular velocity at t = 4.2 w is 6. 17 rad / s

To summerise:

at t = 4.2 s

Angular velocity: 6. 17 rad /s

The number of revolutions: 2.06

3 0

1 year ago

The research of social psychologist Vincent Hsu determined that Americans tend to fulfill their ideal of self-reliance through

dsp73

I think the correct answer from the choices listed above is option C. The research of social psychologist vincent hsu determined that americans tend to fulfill their ideal of self-reliance through <span> developing personal ideals. Hope this answers the question.</span>

3 0

3 years ago

Based on what you learn about jovian moons by watching the videos or reading your textbook, what types of evidence for recent or

Valentin [98]

Answer:

b. craters, river valleys feeding into surface lakes of very cold liquids

Explanation:

Jovian moons are the four largest satellites like the moon of the Jupiter ie the Lo, Europa, Ganymede, Callisto and were first seen by the galileo. They are amiugly the largest moons with radii larger than the dwarf planet.

Lo has more than 400 active volcanoes and dotted more than 100 mountains and has an extremely thin atmosphere made up of sulfur dioxide. The Europa has deep oceans of liquid water, and the layer of ice, and are characteristic of the tidal heating.

<u>While the surface of Callisto is heavily cratered and has salty liquid water.</u>

7 0

3 years ago