Ask question

Ask question

All categories

2 years ago

13

One of the advantages of alternating current (ac) over direct current (dc) is the ease with which voltage levels can be increase

d or decreased.
a. True
b. False

1 answer:

Svet_ta [14]2 years ago

3 0

Answer:

True

Explanation:

In an alternating current, voltage levels can be easily increased or decreased as per the requirements of the energy distribution in practical world.

Hence, the given statement is true

You might be interested in

How are the concepts of impulse and momentum related?

butalik [34]

Answer:

The impulse experienced by the object equals the change in momentum of the object. In equation form, F • t = m • Δ v. In a collision, objects experience an impulse; the impulse causes and is equal to the change in momentum. ... The collision would change the halfback's speed and thus his momentum.

Explanation:

4 0

2 years ago

In the Bronsted-Lowry Theory of acids and bases, an acid is this.

madreJ [45]

Answer: An acid is a substance that donates a proton and produces a conjugate base.

Explanation:

According to Bronsted-Lowry theory, an acid is a substance that donates a proton and produces a conjugate base while a base is a molecule or ion which accepts the proton.

An example of Bronsted-Lowry acid and base is Ethanoic acid, CH3COOH and hydroxide ion, OH- respectively as shown in the reaction below

CH3COOH(aq) + OH-(aq) <---> CH3COO-(aq) + H2O(l)

Thus, ethanoic acid acts as an acid by donating a proton to the hydroxide ion which accepts it, thus producing ethanoate ion, CH3COO- as a conjugate base.

6 0

2 years ago

A stationary police car emits a sound of frequency 1240 HzHz that bounces off of a car on the highway and returns with a frequen

Tju [1.3M]

Answer

given,

frequency from Police car= 1240 Hz

frequency of sound after return = 1275 Hz

Calculating the speed of the car = ?

Using Doppler's effect formula

Frequency received by the other car

$f_1 = \dfrac{f_0(u + v)}{u}$ ..........(1)

u is the speed of sound = 340 m/s

v is the speed of the car

Frequency of the police car received

$f_2= \dfrac{f_1(u)}{u-v}$

now, inserting the value of equation (1)

$f_2= f_0\dfrac{u+v}{u-v}$

$1275=1240\times \dfrac{340+v}{340-v}$

1.02822(340 - v) = 340 + v

2.02822 v = 340 x 0.028822

2.02822 v = 9.799

v = 4.83 m/s

hence, the speed of the car is equal to v = 4.83 m/s

5 0

2 years ago

An object is 15 cm in front of a diverging lens with a

Rainbow [258]

A) See ray diagram in attachment (-6.0 cm)

By looking at the ray diagram, we see that the image is located approximately at a distance of 6-7 cm from the lens. This can be confirmed by using the lens equation:

$\frac{1}{q}=\frac{1}{f}-\frac{1}{p}$

where

q is the distance of the image from the lens

f = -10 cm is the focal length (negative for a diverging lens)

p = 15 cm is the distance of the object from the lens

Solving for q,

$\frac{1}{q}=\frac{1}{-10 cm}-\frac{1}{15 cm}=-0.167 cm^{-1}$

$q=\frac{1}{-0.167 cm^{-1}}=-6.0 cm$

B) The image is upright

As we see from the ray diagram, the image is upright. This is also confirmed by the magnification equation:

$h_i = - h_o \frac{q}{p}$

where $h_i, h_o$ are the size of the image and of the object, respectively.

Since q < 0 and p > o, we have that $h_i >0$ , which means that the image is upright.

C) The image is virtual

As we see from the ray diagram, the image is on the same side of the object with respect to the lens: so, it is virtual.

This is also confirmed by the sign of q in the lens equation: since q < 0, it means that the image is virtual

4 0

2 years ago

two objects are in uniform circular motion at the same speed but at different radii. the ones with the __ radius has the largest

Cerrena [4.2K]

Answer:the one with the smaller radius has the highest centripetal force

Explanation:

5 0

2 years ago

Read 2 more answers