Mexico Mexico language to is the answer to the question
Answer:
Explanation:
<u>Given Data:</u>
Mass = m = 4 kg
Acceleration due to gravity = g = 9.8 m/s²
Height = h = 1 m
<u>Required:</u>
Potential Energy = P.E. = ?
<u>Formula:</u>
P.E. = mgh
<u>Solution:</u>
P.E. = (4)(9.8)(1)
P.E. = 39.2 Joules
Hope this helped!
<h3>~AH1807</h3>
Answer:
Explanation:
a ) starting from rest , so u = o and initial kinetic energy = 0 .
Let mass of the skier = m
Kinetic energy gained = potential energy lost
= mgh = mg l sinθ
= m x 9.8 x 70 x sin 30
= 343 m
Total kinetic energy at the base = 343 m + 0 = 343 m .
b )
In this case initial kinetic energy = 1/2 m v²
= .5 x m x 2.5²
= 3.125 m
Total kinetic energy at the base
= 3.125 m + 343 m
= 346.125 m
c ) It is not surprising as energy gained due to gravitational force by the earth is enormous . So component of energy gained due to gravitational force far exceeds the initial kinetic energy . Still in a competitive event , the fractional initial kinetic energy may be the deciding factor .
Answer:
False
Explanation:
The given statement "Two objects must be in contact for them to exert a force on each other" is not true as there are many types of forces that doesn't require being in contact for exerting a force.
One such example is the gravitational force acting between two bodies. Gravitational force is the force of pull with which a body pulls another body without being in contact.
For two bodies of masses 'M' and 'm' separated at a distance of 'R', the gravitational force is given as:
The gravitational force acts always act between bodies that have mass. The bodies are not in contact yet experience force.
Therefore, the given statement is false.
Answer:
D) Fusion requires high temperatures and pressures, so how have they reduced the energy cost for it?
Explanation:
Fusion requires high temperatures and pressure for initiation of reaction . There is no chain reaction in it so there is no problem of controlling the problem . On the other hand , the reaction tends to stop as soon as temperature goes down due to heat getting dissipated . There is no problem of fuel as its fuel is deuterium which is present in nature in large amount . The question which is pertinent is that the cost involved in attaining so high temperature is very high so is it cost effective to produce energy by incurring so much of cost . Producing energy by using so much of energy in the beginning appears to be preposterous.