We are given that a 20 kg cylindrical mass is dropped onto the mat from a height of 1 m above the mat. During the impact, the cylinder’s vertical velocity reaches zero at the instant the mat has compressed to only 4 cm thick.
So, The Mat gets compressed by : 10cm - 4 cm = 6 cm=0.06 m
a)
Using Conservations of energy
Potential energy at the top = Kinetic energy at the point before touching the surface
Kinetic energy = mgh=
b)
Work done by the mat do to stop the fall of the cylinder =
<span>Let us use the variable x for length. So width will be 1/2x + 3.
Perimeter = x+x+ 1/2x + 3 +1/2x + 3 = 3x + 6 = 66
Therefore 3x = 66-6 = 60
So x = 60/3 = 20
The length is 20 cm.
Therefore the width = 1/2 of 20 + 3 = 10 + 3 = 13 cm
Check: 20+20+13+13 = 66</span>