The box is kept in motion at constant velocity by a force of F=99 N. Constant velocity means there is no acceleration, so the resultant of the forces acting on the box is zero. Apart from the force F pushing the box, there is only another force acting on it in the horizontal direction: the frictional force
which acts in the opposite direction of the motion, so in the opposite direction of F.
Therefore, since the resultant of the two forces must be zero,
so
The frictional force can be rewritten as
where
,
. Re-arranging, we can solve this equation to find
, the coefficient of dynamic friction:
If Frank leaves Gainesville at 7:30 am, the time he should arrive in Tampa is 12.00 pm after spending 4 hours 30 minutes on the road.
<h3>What is average speed? </h3>
The average speed of an object is the ratio of total distance to total time of motion.
V = total distance/total time
For Frank to be in Tampa by noon, he must spend atleast 4 hours 30 minutes on the road.
18.3 mph = d/4.5 h
d = 82.35 miles
The distance between Gainesville and Tampa is 82.35 miles.
Thus, we can conclude that, if Frank leaves Gainesville at 7:30 am, the time he should arrive in Tampa is 12.00 pm after spending 4 hours 30 minutes on the road.
Learn more about average speed here: brainly.com/question/6504879
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Path for transmitting electric current. An electric circuit includes a device that gives energy to the charged particles constituting the current, such as battery or a generator; devices that use current, such as lamps, electric motors, or computers; and the connecting wires or transmission lines
To calculate the change in kinetic energy, you must know the force as a function of position. The work done by the force causes the kinetic energy change
Explanation:
The work-energy theorem states that the change in kinetic enegy of an object is equal to the work done on the object:
where the work done is the integral of the force over the position of the object:
As we see from the formula, the magnitude of the force F(x) can be dependent from the position of the object, therefore in order to solve correctly the integral and find the work done on the object, it is required to know the behaviour of the force as a function of the position, x.
