If the crate shown here is moving at a constant speed in a straight line and the force applied is 310 N, what is the magnitude o
f the force of friction?
A.310 N
B.0 N
C.620 N
A.310 N
B.0 N
C.620 N
1 answer:
Answer:
the answer is A.
Explanation:
Using the laws of newton:
∑F = ma
where ∑F is the sumatory of forces acting in the system, m the mass and a the acelertion of the system.
Then, if the block is moving with constant velocity, its aceleration is equal to 0, so:
∑F = m(0)
∑F = 0
It means that:
F - = 0
where F is the force applied and is the friction force. Replacing the value of F, we get:
310N - = 0
Finally, solving for :
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