Answer:
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The sum of the kinetic and potential energies of a system of objects is conserved only when no external force acts on the objects.
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Conservation of mechanical energy</h3>
The principle of conservation of mechanical energy states that the total mechanical energy of an isolated system (absence of external force) is always constant.
M.A = P.E + K.E
where;
P.E is potential energy
K.E is kinetic energy
Thus, the sum of the kinetic and potential energies of a system of objects is conserved only when no external force acts on the objects.
Learn more about conservation of mechanical energy here: brainly.com/question/24443465
Answer:
this app is for solving doubts not sending links ok
W=20 e(-kt)
A. Rearranging gives k= -(ln(w/20)/t
Substituting w= 10 and solving gives k=0.014
B. Using W=20e(-kt). After 0 hours, W=20. After 24 hours, W=14.29g. After 1 week (24x7=168h) W=1.9g
C. Rearranging gives t=-(ln(10/20)/k. Substituting w=1 and solving gives t=214 hours.
D. Differentiating gives dW/ dt = -20ke(-kt). Solving for t=100 gives dW/dt = 0.07g/h. Solving for t=1000 gives 0.0000002g/h
E. dW/dt = -20ke(-kt). But W=20e(-kt) so dW/dt = -kW
Answer:
The strong person should carry the ladder at the front end and the weak person should carry it at the back end.
Explanation:
this is because in such a case the strong person has to pull the ladder whereas the weak person at the back end have to push the ladder. In such case it is easier to push because the weak person can use the force of gravity of his own body for pushing the ladde.
However in case of pulling the ladder one has to overcome his own gravity to pull the heavy object
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<h2><em>I Hope it help you </em></h2>