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3 years ago

Which of the following is NOT a example

Physics

1 answer:

solmaris [256]3 years ago

5 0

Answer:

B. a piece of paper being torn

Explanation:

A chemical change is one that cannot be reversed. This means the original properties of the substance or object cannot be restored.

If you cook a raw egg, it would turn into a boiled egg (or a poached egg, however it is being cooked). The reaction is irreversible, so you cannot turn the cooked egg back into a raw egg - it is basically impossible to 'uncook' an already cooked egg.

When you toast a piece of bread, it turns into toast. You can't 'untoast' it back into bread. The chemical changes have already occurred and cannot be undone.

If you tear a piece of paper, it is still paper. You are only ripping it, not changing anything about it. You could simply tape the torn bit back to the original bit, or glue it - either way, it is still paper and nothing has occurred to drastically change the physical state of it.

Therefore, B is not a chemical change.

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A student is trying to calculate the density of a can. He already knows the mass, but he needs to determine the volume as well.

elena-14-01-66 [18.8K]

Answer:

V=Bh

Explanation:

B h is used for rectangular solids and cylinders

6 0

3 years ago

in the derivation of the time period of a pendulum in electric field when considering the fbd of bob to find the g effective why

Neko [114]

Answer:

we learned that an object that is vibrating is acted upon by a restoring force. The restoring force causes the vibrating object to slow down as it moves away from the equilibrium position and to speed up as it approaches the equilibrium position. It is this restoring force that is responsible for the vibration. So what forces act upon a pendulum bob? And what is the restoring force for a pendulum? There are two dominant forces acting upon a pendulum bob at all times during the course of its motion. There is the force of gravity that acts downward upon the bob. It results from the Earth's mass attracting the mass of the bob. And there is a tension force acting upward and towards the pivot point of the pendulum. The tension force results from the string pulling upon the bob of the pendulum. In our discussion, we will ignore the influence of air resistance - a third force that always opposes the motion of the bob as it swings to and fro. The air resistance force is relatively weak compared to the two dominant forces.

The gravity force is highly predictable; it is always in the same direction (down) and always of the same magnitude - mass*9.8 N/kg. The tension force is considerably less predictable. Both its direction and its magnitude change as the bob swings to and fro. The direction of the tension force is always towards the pivot point. So as the bob swings to the left of its equilibrium position, the tension force is at an angle - directed upwards and to the right. And as the bob swings to the right of its equilibrium position, the tension is directed upwards and to the left. The diagram below depicts the direction of these two forces at five different positions over the course of the pendulum's path.

that's what I know so far

8 0

3 years ago

A 14.0 gauge copper wire of diameter 1.628 mm carries a current of 12.0 mA . A) What is the potential difference across a 1.80 m

Serga [27]

Answer: a) 139.4 μV; b) 129.6 μV

Explanation: In order to solve this problem we have to use the Ohm law given by:

V=R*I whre R= ρ *L/A where ρ;L and A are the resistivity, length and cross section of teh wire.

Then we have:

for cooper R=1.71 *10^-8* 1.8/(0.001628)^2= 11.61 * 10^-3Ω

and for silver R= 1.58 *10^-8* 1.8/(0.001628)^2=10.80 * 10^-3Ω

Finalle we calculate the potential difference (V) for both wires:

Vcooper=11.62* 10^-3* 12 * 10^-3=139.410^-6 V

V silver= 10.80 10^-3* 12 * 10^-3=129.6 10^-6 V

8 0

4 years ago

Read 2 more answers

Which statement about an atom is correct?

Alexus [3.1K]

Answer:

$\boxed{ \sf{The \: electron \: has \: a \: negative \: charge \: and \: is \: found \: outside \: of \: the \: nucleus}}$

Option A is correct

Explanation:

Let's check the options:

A: The electron has a negative charge and is found outside of the nucleus.

$\mapsto{}$ Yeah! It's TRUE . An electron is a negatively charged particle and is located outside the nucleus of an atom.

B : The neutron has a negative charge and is found in the nucleus.

$\mapsto{}$ No! It's FALSE . A neutron carries no charge. i.e it is a neutral particle and found inside the nucleus.

C : The proton has no charge and is found in the nucleus.

$\mapsto{}$ No! It's FALSE.A proton is a positively charged particle present inside nucleus of an atom.

D : The neutron has no charge and is found outside of the nucleus.

$\mapsto{}$ I agree that the neutron has no charge. But it is found inside the nucleus not outside . So, this statement is FALSE .

Hence, we found our answer! :D

A. The electron has a negative charge and is found outside of the nucleus is the correct statement about an atom.

Hope I helped!

Best regards! :D

~ $\text{TheAnimeGirl}$

7 0

3 years ago

What is a transformer

Leto [7]

A robot character that can transform into a car

6 0

3 years ago

Read 2 more answers