Answer:
it grabs unto soil and keeps it clamped together it prevents this makes the soil harder to wash away
The mechanical energy of an object is the sum of its potential and kinetic energy.
Because the ball is on the ground, its potential energy is 0.
Its kinetic energy is given by:
K.E = 1/2 mv²
K.E = 1/2 x 1 x 2²
K.E = 2 J
Mechanical energy = 2 + 0
Mechanical energy = 2 J
The answer is B.
The component of the crate's weight that is parallel to the ramp is the only force that acts in the direction of the crate's displacement. This component has a magnitude of
<em>F</em> = <em>mg</em> sin(20.0°) = (15.0 kg) (9.81 m/s^2) sin(20.0°) ≈ 50.3 N
Then the work done by this force on the crate as it slides down the ramp is
<em>W</em> = <em>F d</em> = (50.3 N) (2.0 m) ≈ 101 J
The work-energy theorem says that the total work done on the crate is equal to the change in its kinetic energy. Since it starts at rest, its initial kinetic energy is 0, so
<em>W</em> = <em>K</em> = 1/2 <em>mv</em> ^2
Solve for <em>v</em> :
<em>v</em> = √(2<em>W</em>/<em>m</em>) = √(2 (101 J) / (2.0 m)) ≈ 10.0 m/s
<span>Static frictional force = 126.91 N
1st worker force = 110 N
2nd worker = 126.91 – 110 = 16.91 N</span>electron1 <span>· 7 years ago.</span>
