A 2.0-kilogram block sliding down a ramp from a height of 3.0 meters above the ground
reaches the ground with a kinetic energy of 50. joules. The total work done by friction on the
block as it slides down the ramp is approximately
(1) 6 J
(2) 9 J
(3) 18 J
(4) 44 J

The total work done by friction on the block as it slides down the ramp is 44 J.

The given parameters;

mass of the block, m = 2 kgheight of the ramp, h = 3.0 mkinetic of the block, K.E = 50 J

The work done by friction is the change in the mechanical energy of block;

Thus, the total work done by friction on the block as it slides down the ramp is 44 J.

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Is a  vector quantity  that refers to "the rate at which an object changes its position." imagine a person moving rapidly - one step forward and one step back - always returning to the original starting position. while this might result in a frenzy of activity, it would result in a zero velocity. because the person always returns to the original position, the motion would never result in a change in position. since velocity is defined as the rate at which the position changes, this motion results in zero velocity. if a person in motion wishes to maximize their velocity, then that person must make every effort to maximize the amount that they are displaced from their original position. every step must go into moving that person further from where he or she started. for certain, the person should never change directions and begin to return to the starting position.