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2 years ago

Change. Wax melting is an example of a chemical reaction. True or false

Physics

2 answers:

faltersainse [42]2 years ago

6 0

I believe it is a physical change not chemical

Alekssandra [29.7K]2 years ago

4 0

Answer:

False, because here only physical properties are changing.

luv,

Aria❤

You might be interested in

The current in a stream runs at 5 miles per hour. if a boat can go 15 miles per hour on still water, how fast can the boat go do

arsen [322]

Down stream it would be going 20 mph and up stream 10 mph

3 0

3 years ago

Which of the statements concerning light are true? The speed of light is the same no matter what material it is traveling throug

wel

Answer:

The statements that are true concerning light are the last three statements:

Its propagation direction is perpendicular to both the electric field and the magnetic field.

It moves at a constant speed through a vacuum.

The speed of light in matter is less than the speed of light in a vacuum.

Explanation:

Light is electromagnetic waves.

The properties of the electromagnetic waves were established by James Clerk Maxwell.

They included that they are the result of the oscillation of a magnetic field in phase with an electric field which are always is always perpendicular to each other.

Also, the electromagnetic waves propagate at right-angles to the direction of both the magnetic and the electric field, meaning that they are a type of transverse wave.

Thus, the second statement ("Its propagation direction is parallel to both the electric field and the magnetic field") is false, and the fourth statement ("Its propagation direction is perpendicular to both the electric field and the magnetic field") is true.

On the other hand, it is a postulate of the special theory of relativity that the speed of light is a constant (absolute value) in vacuum: nothing can travel faster than what light travels in vacuum. Thus, the fifth statement, "It moves at a constant speed through a vacuum" is true.

About the speed of light in matter, it is always less than the speed of light in vacuum. Thus, the first statement, "the speed of light is the same no matter what material it is traveling through", and the third statement "the speed of light in matter is greater than the speed of light in a vacuum" are false; while the last statement, "the speed of light in matter is less than the speed of light in a vacuum" is true.

The explanation on why the speed of light is less in a medium than in vacuum is related with the fact that at nanoscopic level the waves suffer polarization which means deviations from the straighi path, which makes that the net straight propagation is slower.

8 0

3 years ago

A 0.50 kg toy is attached to the end of a 1.0 m very light string. The toy is whirled in a horizontal circular path on a frictio

xenn [34]

Answer:

The maximum speed will be 26.475 m/sec

Explanation:

We have given mass of the toy m = 0.50 kg

radius of the light string r = 1 m

Tension on the string T = 350 N

We have to find the maximum speed without breaking the string

For without breaking the string tension must be equal to the centripetal force

So $T=\frac{mv^2}{r}$

So $350=\frac{0.5\times v^2}{1}$

$v^2=700$

v = 26.475 m /sec

So the maximum speed will be 26.475 m/sec

6 0

2 years ago

Shrinking Loop. A circular loop of flexible iron wire has an initial circumference of 168 cm , but its circumference is decreasi

DedPeter [7]

Answer:

103.1 V

Explanation:

We are given that

Initial circumference=C=168 cm

$\frac{dC}{dt}=-15cm/s$

Magnetic field,B=0.9 T

We have to find the magnitude of the emf induced in the loop after exactly time 8 s has passed since the circumference of the loop started to decrease.

Magnetic flux= $\phi=BA=B(\pi r^2)$