You move a 75-kg box 35 m. This requires a force of 90 N. how much work is done while moving the box?
1 answer:
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Answer:
-4.0 N
Explanation:
Since the force of friction is the only force acting on the box, according to Newton's second law its magnitude must be equal to the product between mass (m) and acceleration (a):
(1)
We can find the mass of the box from its weight: in fact, since the weight is W = 50.0 N, its mass will be
And we can fidn the acceleration by using the formula:
where
v = 0 is the final velocity
u = 1.75 m/s is the initial velocity
t = 2.25 s is the time the box needs to stop
Substituting, we find
(the acceleration is negative since it is opposite to the motion, so it is a deceleration)
Therefore, substituting into eq.(1) we find the force of friction:
Where the negative sign means the direction of the force is opposite to the motion of the box.
Answer:
the velocity of the water flow is 7.92 m/s
Explanation:
The computation of the velocity of the water flow is as follows
Here we use the Bernouli equation
As we know that
= 7.92 m/s
Hence, the velocity of the water flow is 7.92 m/s
We simply applied the above formula so that the correct value could come
And, the same is to be considered