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3 years ago

Which of the following is an example of heat convection?

Physics

2 answers:

lora16 [44]3 years ago

8 0

I believe it’s a liquid inside a beaker on a hot Bunsen burner (c)

This is because : Everyday Examples of Convection
Boiling water - The heat passes from the burner into the pot, heating the water at the bottom. Then, this hot water rises and cooler water moves down to replace it, causing a circular motion. Radiator - Puts warm air out at the top and draws in cooler air at the bottom.

Not sure if it’s right tho!

olya-2409 [2.1K]3 years ago

8 0

Answer:

Liquid inside a beaker on a hot Bunsen burner circulates and heats through constant motion.

Explanation:

Transmission of heat by convection requires the movement of a liquid or gas. An example would be liquid in a beaker heating up as hot and cold parts of the liquid constantly circulate, which further heats the liquid. Heat from the sun is considered radiation, and the other two answers are examples of conduction.

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Why do things become hot or cold? Relate to Thermal Energy and The Law of Conservation of Energy

Mekhanik [1.2K]

Answer:

Things become hot and cold because of the transfer of energy.

Explanation:

The energy possessed by an object or system is called thermal energy and heat is the flow of this energy. While the law of conversation of energy states that energy is not destroyed or created, it just transfers from one object to another.

When a hot object is placed in normal conditions, it transfers heat to the environment until both are at the same temperature and heat transfers from the environment to the cold objects placed in normal conditions.

4 0

3 years ago

Which material is used to reduce friction ?

Iteru [2.4K]

Answer:MOST COMMON METHOD IS USING A LUBRICANT -

A lubricant is a substance, usually organic, introduced to reduce friction between surfaces in ... medical examination. It is mainly used to reduce friction and to contribute to a better and efficient functioning of a mechanism. ... For lubricant base oil use, the vegetable derived materials are preferred

OTHER METHODS-

There are a number of ways to reduce friction:

Make the surfaces smoother. ...

Lubrication is another way to make a surface smoother.

Make the object more streamlined.

Reduce the forces acting on the surfaces.

Reduce the contact between the surfaces.

PLEASE DO MARK ME AS THE BRAINLIEST :)

6 0

3 years ago

Sketch a reaction progress curve for a reaction that has an activation energy of 22 kj and the total energy change is -103kj.

crimeas [40]

Answer:

Do find the answer in the attachment herein.

Explanation:

From the attached diagram:

I. Activation energy = Activated complex - ∆H(reactants)

Activation energy = 162-140 = 22Kj.

II. ∆H(reaction) = ∆H(products) - ∆H(reactants)

∆H(reaction) = 37 - 140 = -103Kj.

8 0

3 years ago

Two identical resistors are connected in parallel across a 26-V battery, which supplies them with a total power of 7.1 W. While

Gnom [1K]

Answer:

A) R = 190.42 Ω

B) P = 5.325 W

Explanation:

We are given;

Total power;P_tot = 7.1 W

Voltage;V = 26 V

A)We are told that while the battery is still connected, one of the resistors is heated, so that its resistance doubles.

Thus, the power is doubled.

Now, formula for power is;

P = IV

Thus, since power is doubled, we have;

P = 2(IV)

Now, formula for current is; I = V/R

So, P = 2V²/R

Making R the subject, we have;

R = 2V²/P

In this question, P is p_total = 7.1 W

Thus;

R = (2 × 26²)/7.1

R = 190.42 Ω

B) Now, the resistance of the resistors are R and 2R.

Formula for power in this context is;

P = V²/R

Thus,

Total power delivered to the resistors is;

P = V²/R + V²/2R

P = 3V²/2R

P = (3 × 26²)/(2 × 190.42)

P = 5.325 W

8 0

3 years ago

What motivates the squire in lines 85- 90?

just olya [345]

Answer: If you mean the Knight in the prologue, the man traveling with his son (the Squire) and a Yeoman, he is traveling to Canterbury to give thanks for his safe return from the wars in the Baltic. We're told that he has never been known to speak unkindly to anyone, a fact that sums up his chivalrous upbringing. Evidently he feels strongly motivated to live by a code of high standards and refined behavior.

5 0

3 years ago