Answer:
14112 J
Explanation:
When the 72 Kg mass explodes into two, one mass is twice the other so 72/3=24 Kg
M1= 24 kg, M2= 72-24=48 kg
From law of conservation of linear momentum, the sum of initial and final momentum are equal. p=mv where p is momentum, m is mass and v is velocity. Fir this case, since the less massive piece stops, its final velocity is zero.
72*28=48v2
V2=72*28/48=42 m/s
Difference between initial and final kinetic energy will be

Therefore, from observers reference, kinetic energy of 14112 J is added
Answer:
hi you can just buy new ruler lol joke
1. energy and air
2.
Answer:
Explanation:
This is an RL circuit, therefore:
Impedance; z = 

Current amplitude

a)
Given that:

∴


b)
Phase constant :


Answer:
True.
Explanation:
Energy can be defined as the ability (capacity) to do work. The two (2) main types of energy are;
a. Gravitational potential energy (GPE): it is an energy possessed by an object or body due to its position above the earth.
b. Kinetic energy (KE): it is an energy possessed by an object or body due to its motion.
Furthermore, the mechanical energy of a physical object or body is the sum of the potential energy and kinetic energy possessed by the object or body.
Mathematically, it is given by the formula;
Mechanical energy = G.P.E + K.E
Mechanical energy that has been ‘lost' to friction isn't really lost. It just is no longer in its mechanical form. This is ultimately in accordance with the law of conservation of energy, which states that energy cannot be destroyed but can only be converted or transformed from one form to another.
Hence, Mechanical energy that has been ‘lost' to friction isn't really lost but converted into heat energy.
Answer:
Explanation:
It is required that the weight of Joe must prevent Simon from being pulled down . That means he is not slipping down but tends to be towed down . So in equilibrium , force of friction will act in upward direction on Simon.
Let in equilibrium , tension in rope be T
For balancing Joe
T = M g
For balancing Simon
friction + T = mgsinθ
μmgcosθ+T = mgsinθ
μmgcosθ+Mg = mgsinθ
M = (msinθ - μmcosθ)
M = m(sinθ - μcosθ)