Which of the following is not an assumption of stage theories?

Uses of Photodiode.State the 8 uses of phototide...................

Inessa05 [86]

Answer:

Photodiodes are used in consumer electronics devices such as compact disc players, smoke detectors, medical devices and the receivers for infrared remote control devices used to control equipment from televisions to air conditioners. For many applications either photodiodes or photoconductors may be used.

6 0

3 years ago

A negative test charge experiences a force to the right as a result of an electric field. Which is the best conclusion to draw

Alona [7]

Answer:a

Explanation:

4 0

3 years ago

A bird sitting on the limb of a tree is moving about 30 km/s with respect to the Sun. If the bird takes 1 second to drop down to

Alexandra [31]

Answer:

This faulty reasoning is best countered with Newton's First Law.

Explanation:

Newton's First Law states that every object or body will remain in its state, be it of rest or uniform motion, unless it is affected by a force.

This means that even while sitting, we are all moving at extreme speeds with respect to the Sun, of approximately 30 km/s (yes, including the bird and the worm), but we don't even notice because we are all moving at approximately the same speed, and we aren't being affected by a force strong enough that could change our state of being in said extreme speed with respect to the Sun (that is, unless our Earth suddenly stopped moving around the Sun!).

With that being said, when the bird drops down from the limb of the tree, it moves by "adding" a vertical speed from the tree to the ground, but, in reality, the bird is still moving at 30 km/s in a given axis with respect to the Sun, as well as the worm. Now, since the worm didn't "add" a speed to move away from the bird (or, at least, we assume that's what happened), the bird finally catches the worm.

To sum it all up: Yes, the worm still moves at 30 km/s with respect to the Sun, but the bird moves at the same speed, PLUS a given speed from the tree to the ground that helps it get to the worm.

7 0

3 years ago

A cylinder with rotational inertia I1=2.0kg·m2 rotates clockwise about a vertical axis through its center with angular speed ω1=

Mrac [35]

Answer:

a) 0.67 rad/sec in the clockwise direction.

b) 98.8% of the kinetic energy is lost.

Explanation:

Let us take clockwise angular speed as +ve

For first cylinder

rotational inertia $I$ = 2.0 kg-m^2

angular speed ω = +5.0 rad/s

For second cylinder

rotational inertia $I$ = 1.0 kg-m^2

angular speed = -8.0 rad/s

The rotational momentum of a rotating body is given as = $I$ ω

where $I$ is the rotational inertia

ω is the angular speed

The rotational momenta of the cylinders are:

for first cylinder = $I$ ω = 2.0 x 5.0 = 10 kg-m^2 rad/s

for second cylinder = $I$ ω = 1.0 x (-8.0) = -8 kg-m^2 rad/s

The total initial angular momentum of this system cylinders before they were coupled together = 10 + (-8) = 2 kg-m^2 rad/s

When they are coupled coupled together, their total rotational inertia $I_{t}$ = 1.0 + 2.0 = 3 kg-m^2

Their final angular rotational momentum after coupling = $I_{t}$ $w_{f}$

where $I_{t}$ is their total rotational inertia

$w_{f}$ = their final angular speed together

Final angular momentum = 3 x $w_{f}$ = 3 $w_{f}$

According to the conservation of angular momentum, the initial rotational momentum must be equal to the final rotational momentum

this means that

2 = 3 $w_{f}$

$w_{f}$ = final total angular speed of the coupled cylinders = 2/3 = 0.67 rad/s

From the first statement, the direction is clockwise

b) Rotational kinetic energy = $\frac{1}{2} Iw^{2}$

where $I$ is the rotational inertia

$w$ is the angular speed

The kinetic energy of the cylinders are:

for first cylinder = $\frac{1}{2} Iw^{2}$ = $\frac{1}{2}*2*5^{2}$ = 25 J

for second cylinder = $\frac{1}{2}*1*8^{2}$ = 32 J

Total initial energy of the system = 25 + 32 = 57 J

The final kinetic energy of the cylinders after coupling = $\frac{1}{2}I_{t}w^{2} _{f}$

where

where $I_{t}$ is the total rotational inertia of the cylinders

$w_{f}$ is final total angular speed of the coupled cylinders

Final kinetic energy = $\frac{1}{2}*3*0.67^{2}$ = 0.67 J

kinetic energy lost = 57 - 0.67 = 56.33 J

percentage = 56.33/57 x 100% = 98.8%

6 0

3 years ago

Decribe what makes a diamand a mineral

RUDIKE [14]

Very very very high pressures, very etc high temperatures, varying degrees of "carbon purity" and a long time make diamonds diamonds. Minerals ? Well, every so often, should you be lucky, or live in South Africa you might come across one. (Let me know if you do).

7 0

3 years ago