While playing Quidditch you throw the quaffle straight down to the person below you at

Which choice most accurately defines resistance and voltage of a circuit?

devlian [24]

Answer:

c

Explanation:

did the test :)

7 0

2 years ago

The drive chain in a bicycle is applying a torque of 0.850 nm to the wheel of the bicycle. treat the wheel as a hoop with a mass

BlackZzzverrR [31]

The equivalent of Newton's second law for rotational objects is given by:
$\tau = I \alpha$
where
$\tau$ is the net torque acting on the object
$I$ is its moment of inertia
$\alpha$ is its angular acceleration

For a hoop rotating around its perpendicular axis, the moment of inertia is
$I=mr^2$
where m is the mass and r the radius. By using the data of the wheel, m=0.750 kg and r=33.0 cm=0.33 m, we find
$I=mr^2 = (0.750 kg)(0.33 m)^2=0.082 kg m^2$

and since the torque is $\tau=0.850 Nm$ , the angular acceleration of the wheel is
$\alpha= \frac{\tau}{I}= \frac{0.850 Nm}{0.082 km m^2}=10.37 rad/s^2$

6 0

3 years ago

. A light bulb glows because of it’s resistance, and the brightness of the bulbincreases with the electrical power delivered to

sesenic [268]

Complete Question

The complete question is shown in the first uploaded image

Answer:

a

When the both bulb are in the circuit bulb B glows equally brighter to bulb A

This because the power delivered to the both bulb are equal

b

The bulb A on the right will glow brighter than the bulb A on the left due to the fact that the power supplied to bulb A on the right is higher than that gotten by bulb A on the left.

Explanation:

From the question we are been told that the two bulbs are identical

So their resistance denoted by R is the same

Considering the left circuit where the two bulbs are connected in series which mean that the same current is passing through them

$R_A =R_B =R$

$i_A = i_B =i$

$R_{eq} = R_1 +R_2 = 2R$

$i = \frac{V}{2R}$

The power that is been deposited on the circuit is evaluated as

$P_A = i^2R$

$P_A = \frac{V^2}{4R}$

$P_B = i^2R$

$P_B = \frac{V^2}{4R}$

For the fact that the power deposited on the bulbs are the same they will glow equally

When B is now removed and only A is left

$R_{eq} = R_A = R$

$i = \frac{V}{R}$

$P'_A = i^2R$

$P'_A = \frac{V^2}{R}$

For the fact that its only bulb A that is on that right circuit the power delivered to it would be greater compared to the left circuit bulb A

7 0

2 years ago

A projectile is shot directly away from Earth's surface. Neglect the rotation of the Earth. What multiple of Earth's radius RE g

Airida [17]

Answer:

Explanation:

Given that,

We have a projectile that is shot from the earth

Then, it's escape velocity is

Ve = √(2GM / R)

Ve² = 2GM / R

M is the mass of earth

R is the radius of Earth

Using conservation of energy

Ki + Ui = Kf + Uf

The final kinetic energy is zero since the body is finally at rest

Then,

Ki + Ui = Uf

Kinetic energy can be determine using

K = ½mv²

Potential energy can be determine using

U = -GmM / R

Where m is mass of the body

Then,

Ki + Ui = Uf

½mv² - GmM / R = -GmM / r

r is the maximum height reached

m cancel out

½ v² - GM / R = -GmM / r

A. We want to find the maximum height reached when initial speed (v) is equal to 0.785 escape velocity

So, v = 0.785•Ve

So,

½v² - GM / R = -GM / r

½(0.785•Ve)² - GM / R = -GM / r

0.308•Ve² - GM / R = -GM / r

0.308 × 2GM / R - GM / R = -GM / r

Divide through by GM

0.616 / R - 1 / R = -1 / r

-0.384 / R = -1 / r

Cross multiply

-0.384r = -R

r = -R / -0.384

r = 2.6 R

B. When it initial kinetic energy is is 0.785 of the kinetic energy required to escape Earth

Ki = 0.785 Ke

Ki = 0.785 ½mVe²

Ki = 0.785 × ½m× 2GM / R

Ki = 0.785•G•m•M / R

So,

Ki + Ui = Uf

0.785•G•m•M / R - GmM / R = -GmM / r

Let G•m•M cancels out

0.785 / R - 1 / R = -1 / r

-0.215 / R = -1 / r

Cross multiply.

-0.215r = -R

r = -R / -0.215

r = 4.65 R

7 0

3 years ago

PLZ HELP ASAP! 2.03 QUIZ: TEMPERATURE AND HEAT

gladu [14]

A. Its A for sure but I don't like the way it's written here, they didn't get the physics right

The temperature increases BECAUSE the kinetic energy of the molecules increases

7 0

2 years ago