Question 8

The difference between an electric motor and an electric generator is that a motor converts _______ energy into energy _______,

lianna [129]

Answer:

Motor converts Electrical energy into Mechanical Energy, while A generator converts Mechanical energy into Electrical energy. thankyou

Explanation:

3 0

3 years ago

Read 2 more answers

A 15.0-mW laser puts out a narrow beam 2.00 mm indiameter.

UkoKoshka [18]

Explanation:

It is known that formula for energy per unit area per unit time is as follows.

S = $\frac{P}{A}$

= $\frac{P}{\pi \times r^{2}} = \frac{4P}{\pi d^{2}}$

$c \epsilon_{o} E^{2} = \frac{4P}{\pi d^{2}}$

E = $\sqrt{\frac{4P}{\pi d^{2} c \epsilon_{o}}}$

Now, putting the values we will calculate the electric field as follows.

E = $\sqrt{\frac{4P}{\pi d^{2} c \epsilon_{o}}}$

= $\sqrt{\frac{4 \times 15 \times 10^{-3} W}{3.14 \times (2mm \times \frac{1m}{1000 mm})^{2} \times 3 \times 10^{8} \times 8.85 \times 10^{-12}}}$

= 1341.03 V/m

Now, we will calculate the average magnetic field as follows.

B = $\frac{E}{c}$

= $\frac{1341.03 V/m}{3 \times 10^{8} m/s}$

= $4.47 \times 10^{-6}$ T

= $4.47 \mu T$

Thus, we can conclude that the average (rms) value of the magnetic field is $4.47 \mu T$ .

3 0

3 years ago

a cyclist applies a constant forward force of 20 N to maintain a velocity 2.5 m/s. how much power does the cyclist deliver?

forsale [732]

The power exerted by the cyclist is determined as 50 W.

<h3>Average power exerted by the cyclist</h3>

The power exerted by the cyclist is calculated as follows;

P = FV

where;

F is the applied force
V is velocity

P = 20 x 2.5

P = 50 W

Thus, the power exerted by the cyclist is determined as 50 W.

Learn more about power here: brainly.com/question/25263760

#SPJ1

4 0

2 years ago

Which is an example of a chemical change?

Deffense [45]

Burning a log of wood is an example of a chemical change

5 0

3 years ago

The following questions present a twist on the scenario above to test your understanding. Suppose another stone is thrown horizo

Ipatiy [6.2K]

The first part of the text is missing, you can find on google:

"A ball is thrown horizontally from the roof of a building 45 m. If it strikes the ground 56 m away, find the following values."

Let's now solve the different parts.

(a) 3.03 s

The time of flight can be found by analyzing the vertical motion only. The vertical displacement at time t is given by

$y(t) = h -\frac{1}{2}gt^2$

where

h = 45 m is the initial height

g = 9.8 m/s^2 is the acceleration of gravity

When y=0, the ball reaches the ground, so the time taken for this to happen can be found by substituting y=0 and solving for the time:

$0=h-\frac{1}{2}gt^2\\t=\sqrt{\frac{2h}{g}}=\sqrt{\frac{2(45)}{9.8}}=3.03 s$

(b) 18.5 m/s

For this part, we need to analyze the horizontal motion only, which is a uniform motion at constant speed.

The horizontal position is given by

$x=v_x t$

where

$v_x$ is the horizontal speed, which is constant

t is the time

At t = 3.03 s (time of flight), we know that the horizontal position is x = 56 m. By substituting these numbers and solving for vx, we find the horizontal speed:

$v_x = \frac{x}{t}=\frac{56}{3.03}=18.5 m/s$

The ball was thrown horizontally: this means that its initial vertical speed was zero, so 18.5 m/s was also its initial overall speed.

(c) 35.0 m/s at 58.1 degrees below the horizontal

At the impact, we know that the horizontal speed is still the same:

$v_x = 18.5 m/s$

we need to find the vertical velocity. This can be done by using the equation

$v_y = u_y -gt$

where

$u_y =0$ is the initial vertical velocity

g is the acceleration of gravity

t is the time

Substituting t = 3.03 s, we find the vertical velocity at the time of impact:

$v_y = -(9.8)(3.03)=-29.7 m/s$

So the magnitude of the velocity at the impact (so, the speed at the impact) is

$v=\sqrt{v_x^2+v_y^2}=\sqrt{18.5^2+(-29.7)^2}=35.0 m/s$

The angle instead can be found as:

$\theta=tan^{-1}(\frac{v_y}{v_x})=tan^{-1}(\frac{-29.7}{18.5})=-58.1^{\circ}$

so, 58.1 degrees below the horizontal.

4 0

3 years ago