Question
Starting from rest, a 4.4 kg block slides 3.5 m down a rough 22.3o incline in 2.4 seconds. Determine the energy lost due to friction. (Hint: find the final kinetic energy and subtract that from the work done by gravity.)
Enter your answer here: J
Enter your answer here: J
Answers
drwls
Your hint tells you how to do it.
The final velocity is twice the average velocity of 3.5/2.4 m/s, which would be
Vfinal = 2.92 m/s
Energy lost = M g H - (1/2) M Vfinal^2/2
You do not need to use the slope of the incline to get the answer. You COULD use it to get the kinetic friction coefficient.
The final velocity is twice the average velocity of 3.5/2.4 m/s, which would be
Vfinal = 2.92 m/s
Energy lost = M g H - (1/2) M Vfinal^2/2
You do not need to use the slope of the incline to get the answer. You COULD use it to get the kinetic friction coefficient.
bobpursley
average velocity= distance/time=3.5/2.4 m/s
so final velocity= 2*averagevelociyt
and KEfinal= 1/2 m vf^2
height of ramp= 3.5sin22.3
mgh=you figure.
energy from friction= mgh- KEfinal
so final velocity= 2*averagevelociyt
and KEfinal= 1/2 m vf^2
height of ramp= 3.5sin22.3
mgh=you figure.
energy from friction= mgh- KEfinal