Answer:
The speed of the block is 8.2 m/s
Explanation:
Given;
mass of block, m = 2.1 kg
height above the top of the spring, h = 5.5 m
First, we determine the spring constant based on the principle of conservation of potential energy
¹/₂Kx² = mg(h +x)
¹/₂K(0.25)² = 2.1 x 9.8(5.5 +0.25)
0.03125K = 118.335
K = 118.335 / 0.03125
K = 3786.72 N/m
Total energy stored in the block at rest is only potential energy given as:
E = U = mgh
U = 2.1 x 9.8 x 5.5 = 113.19 J
Work done in compressing the spring to 15.0 cm:
W = ¹/₂Kx² = ¹/₂ (3786.72)(0.15)² = 42.6 J
This is equal to elastic potential energy stored in the spring,
Then, kinetic energy of the spring is given as:
K.E = E - W
K.E = 113.19 J - 42.6 J
K.E = 70.59 J
To determine the speed of the block due to this energy:
KE = ¹/₂mv²
70.59 = ¹/₂ x 2.1 x v²
70.59 = 1.05v²
v² = 70.59 / 1.05
v² = 67.229
v = √67.229
v = 8.2 m/s
Physical Change
characteristic is the chemical bonds in the substance are unchanged. Because
a physical change is any change happens in an object but without involving
a change in its chemical substance. Example, Solid to liquid change or
also known as melting, liquid to gas change also known as evaporation, gas
to solid change also known as deposition, liquid to solid or
solidification, solid to gas or sublimation, and gas to liquid or
condensation. The physical form of a substance is change into a new form
but the chemical is unchanged.
<u>D.</u>
For every action ther is an equal and opposite reaction.
equal in force, opposite in direction
Linear momentum is in a straight line and depends on the objects mass and velocity.
Angular (rotational) momentum depends on the objects mass, velocity, and radius.
If Juan used a Celsius thermometer, it would tell him the Celsius temperature.
If he added 273 to that number, he'd have the "absolute" or Kelvin temperature.
