Friction is the force you get when you (for example) Rub something with another, it's a force that may generate heat and even some resistance. Another example is rubbing your hands together, they get hot, therefore friction is working, without friction you wouldn't be able to stop moving.
Cars are the mechanical device which convert chemical energy of fuel into mechanical energy, the engine used in the automobiles car are very inefficient, they can only convert 30-40% of chemical energy of fuel into mechanical energy, since thermodynamics is the branch of science that deals with the conversion of energy, thus due to poor conversion rate of chemical energy into mechanical energy, cars are known as inefficient machine.
Missing question in the text:
"A.What are the magnitude and direction of the electric field at the point in question?
B.<span>What would be the magnitude and direction of the force acting on a proton placed at this same point in the electric field?"</span>
<span>Solution:
A) A charge q </span>under an electric field of intensity E will experience a force F equal to:

In our problem we have
and
, so we can find the magnitude of the electric field:

The charge is negative, therefore it moves against the direction of the field lines. If the force is pushing down the charge, then the electric field lines go upward.
B) The proton charge is equal to

Therefore, the magnitude of the force acting on the proton will be

And since the proton has positive charge, the verse of the force is the same as the verse of the field, so upward.
Answer:
Electric current.
Explanation:
The energy result from electric current resulting from potential differences between terminals which form an Electric circuit. This energy could come from different sources like chemical, wind, light
An electric circuit is one where there is movement of electrons;this electrons acquire charge which is energy. The electrons flow due to a potential difference; you have heard water flows from a higher position to a lower one freely. The highest height is said to be at higher potential and the lower point low potential.
So it's the same with electrons.
The formular for energy on charge is Q= I × t where I is electric current and t is time.
Wave power can be regarded as a reliable source of energy because the ocean currents are always moving.
<h3>What can be the challenges of wave power?</h3>
Wave power is a device that can be used to convert the mechanical energy of the ocean waves into electrical energy based on the principle of conservation of energy.
The major challenges that face the use of wave power in electricity generation is the unreliability of the waves which leads to uncertainty in the quantity of power generated Also, the wave direction and direction of ocean currents all limit the amount of power generated by this method. However, in spite of challenges, it can be regarded as a reliable source of energy because the ocean currents are always moving.
Learn more about wave power:brainly.com/question/1362067
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