Well, Air resistance is a special type of friction (you cannot classify it in other categories). That force of air-resistance is often observed to oppose the motion of the object,( like every other frictional forces)
Hope this helps!
Answer:
<h2>
96 Joules</h2>
Explanation:
We know that efficiency is the ratio of output power by input power. i.e. Efficiency describes the quality of machine or system how good it is.
Solution,
Energy input of system = 120 J
Efficiency = 80% = 
Now,
According to definition,
Efficiency = 
Cross multiplication:

Calculate the product

Hope this helps...
Good luck on your assignment...
Newtons law of motion for every action there’s an equal and opposite reaction.
Answer:
External force on him will be 112 N
Explanation:
We have given the mass of the sprinter m =70 kg
Acceleration of the sprinter 
We have to find the net external force
According to second law of motion force = mass ×acceleration
Force is dependent on the mass and acceleration
So 
So external force will be 112 N
Answer:
It is formed by a horizontal number line, called the x-axis, and a vertical number line, called the y-axis.
Explanation: