Statements A, B, and C are true.
Statement <em> D is false</em>.
Since the track is friction less, block’s kinetic energy at the bottom of the track is equal to its potential energy at the top of the track.
PE = 81 * 9.8 * 3.8 = 3016.44 J
Work = 1/2 * 1888 * d^2
PE = Kinetic energy at the base.
1/2 * 1888 * d^2 = 3016.44
d = 1.78 approx 1.8
F = Ke = 1888 * 1.8 = 3398.4N
Answer:
<h2>4.9N approx.</h2>
Explanation:
Step one:
given data
length of rod r= 2.25m
Required torque = 11 Nm
Required
The force needed to produce a torque of 11Nm
Step two:
<em>"By definition, Torque is the twisting force that tends to cause rotation. </em>
<em>The point where the object rotates is known as the axis of rotation."</em>
Mathematically,

= torque
r = radius
F = force
= angle between F and the lever arm
in this case is zero

substituting we have
F=11/2.25
F=4.88N
F=4.9N approx.
Answer:
they were hunter gatherers
Explanation: