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Snezhnost [94]
3 years ago
6

21. A 60 kg student on a scooter is pushed with a constant force of 40 N across a horizontal concrete driveway at a constant spe

ed of 2 m/s. What is the magnitude of the force of friction that acts against the wheels of the scooter?
Physics
1 answer:
DedPeter [7]3 years ago
3 0

The magnitude of the force of friction is 40 N

Explanation:

To solve the problem, we just have to analyze the forces acting on the student and the scooter along the horizontal direction. We have:

- The constant pushing force forward, of magnitude F = 40 N

- The frictional force, acting backward, F_f

Since the two forces are in opposite direction, the equation of motion is

F-F_f = ma

where

m is the mass of the student+scooter

a is the acceleration

However, here the scooter is moving at constant speed: this means that its acceleration is zero, so

a = 0

And therefore,

F - F_f = 0\\F_f = F

which means that the magnitude of the force of friction is also equal to 40 N.

Learn more about force of friction here:

brainly.com/question/6217246

brainly.com/question/5884009

brainly.com/question/3017271

brainly.com/question/2235246

#LearnwithBrainly

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