2 years ago

How do dog whistles work?

1 answer:

7 0

<em>The sound it emits comes from what is known as the ultrasonic range, a pitch that is so high humans can't hear it. Dogs can hear these sounds, however, as can cats and other animals. Because of this, the dog whistle is a favored training tool, though it may not be for every dog parent.</em>

You might be interested in

What is the common name for tropospheric ozone

Galina-37 [17]

Ozone in troposphere is also know as Bad Ozone, Evil Ozone and Ground Level Ozone.

5 0

3 years ago

Why do electrons move from the negative end of the tube to the positive end

defon

Due to attraction ... of opposite charges

3 0

2 years ago

What can be found in a compost bin?

BigorU [14]

D. all of the above

Hope this helps!

5 0

3 years ago

Read 2 more answers

A starship blasts past the earth at 2.0*10^8 m/s .Just after passing the earth, the starship fires a laser beam out its back of

Vilka [71]

Answer:

at the speed of light ( $c=3.0\cdot 10^8 m/s$ )

Explanation:

The second postulate of the theory of the special relativity from Einstein states that:

"The speed of light in free space has the same value c in all inertial frames of reference, where $c=3.0\cdot 10^8 m/s$ "

This means that it doesn't matter if the observer is moving or not relative to the source of ligth: he will always observe light moving at the same speed, c.

In this problem, we have a starship emitting a laser beam (which is an electromagnetic wave, so it travels at the speed of light). The startship is moving relative to the Earth with a speed of 2.0*10^8 m/s: however, this is irrelevant for the exercise, because according to the postulate we mentioned above, an observer on Earth will observe the laser beam approaching Earth with a speed of $c=3.0\cdot 10^8 m/s$ .

7 0

3 years ago

A man climbs a wall that has a height of 8.4 meters and gave the potential energy of 4620 joules. His mass is about_____ kilogra

Dmitrij [34]

Gravitational potential energy = mass x acceleration due to gravity x height
GPE=mgh
4620=mx9.81x8.4
4620/(9.81x8.4)=m=56.1 kg

7 0

2 years ago