Question

A box with mass m = 8 kg is pushed x = 10 m across a level floor by a constant applied force F P = 16.27 N. The coefficient of kinetic friction between the box and the floor is 0.15 . A box of mass m rests on a horizontal surface. A force F subscript p directed horizontally to the right acts on the box. The box travels a distance x to the right. Assuming the box starts from rest, what is the final velocity of the box at the 10 m point? final velocity: m / s If there were no friction between the box and the floor, what applied force would be required to give the box the same final velocity as previously calculated? applied force:

Answer 1

Answer:

Final speed of the box after it has moved to x = 10 is given as

v = 3.35 m/s

Explanation:

As we know by work energy theorem that work done by all the forces is equal to the change in its kinetic energy

Here work done by external force + work done by friction = change in kinetic energy of the box

so we have

$W_{ex} + W_{fric} = \frac{1}{2}mv^2$

$F x - \mu mg x = \frac{1]{2}mv^2$

$16.27 (10) - (0.15)(8)(9.8) (10) = \frac{1}{2}(8) v^2$

$162.7 - 117.6 = 4 v^2$

$v = 3.35 m/s$