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As Energy is a conservative Force, the total Energy of a system is the Potential Energy plus the Kinetic Energy.
In terms of gravity, the Potential Energy, U, is the mass of an object times the acceleration due to gravity times the height of the object: U = m * g * h.
The Kinetic Energy is one-half the mass of the object times the square of its velocity: K = 1/2 * m * v2
The equation, then, is E = U + K.
An example:
If an object of 50 kg is suspended, at rest, 100 m above Earth, the equation will be U + K = 0, since it is not moving. Then, to solve:
U + K = 0 => U = - K => m * g * h = - 1/2 * m * v2
the mass of the object will cancel, and we'll round gravity to 10 m/s2, giving us
10 m/s2 * 100 m = - 1/2 * v2 => - 2 * 1000 m2/s2 = v2
v2 = - 2000 m2/s2 => v = 44.72 m/s
The negative sign does not indicate a negative velocity, but the direction of the velocity vector, in this case, down.
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How do find gpe when you have velocity?
Assuming the object is travelling vertically (up/down) exclusively:The upward motion comes from kinetic energy, which is dependent on velocity. That kinetic energy is converted to potential energy, so you can set kinetic energy equal to potential energy.Let U = potential energy (in Joules), K = kinetic energy (in Joules)U = mgh, where m is mass, g is the acceleration of gravity, and h is heightK = (1/2)mv2, where v is velocitySolve for U:U = KU = (1/2)mv2That is thesimplestcase. Velocity is a vector (meaning it has direction as well as a magnitude) and it could be moving in a diagonaldirection. You'll have to use yourtrigonometryknowledge to solve these cases.
What do you know about interconversion of energy of kinetic energy and potential energy of free falling bodies?
The potential energy decreases as the body falls while the kinetic energy increases. P.E.=mass x gravity x height The shorter the height the less potential energy there is K.E.= 1/2 x mass x velocity^2 The velocity increases as the body falls and the bigger the velocity the more Kinetic Energy produced
How do you find change in velocity?
when using energy use the kinetic energy equation for change KE = .5(M)(Vf^2 - Vo^2) M = mass Vf = fianal velocity Vo = initial velocity
What type of energy does sitting use?
potential
What is the name for energy that is not in use?
Potential Energy
What is the energy that is stored and available to use?
Potential Energy
What kind of energy might be saved up for future use?
potential energy
Can an object have both potential and kinetic energy at the same?
Yes. Example: A ball thrown directly upwards; at any moment (except at its maximum height) it has velocity, and therefore kinetic energy. Also, at any moment (except when it touches the floor) it has gravitational potential energy (assuming you use the ground level as reference level).
How can you find the kinetic energy without velocity in the question?
The exact method depends on how the question is phrased, but the majority of solutions will involve a conservation of energy. Since the energy of a system must always be conserved, you can determine the change in an objects kinetic energy by measuring how much potential energy it has lost. The most common examples include gravitational potential energy and free fall. For example, say you wanted to find the kinetic energy of a 10kg rock after it has fallen off a cliff 200m high once it has fallen 100 meters. First, you use the formula PE=m*g*h (where m is mass, g is the acceleration due to gravity, 9.81 m/s², and h is the distance above ground). At the top the rock is 200m up, so its potential energy is 10kg*9.81m/s²*200m = 19620J. When the rock has fallen 100 meters, it is 100 meters up, so its potential energy is 10kg*9.81m/s²*100m = 9810J. Now, to find how much kinetic energy the rock has, just calculate the change in potential energy or 19620J-9810J=9810J. The same process can be used when working with chemical, electric, or any other form of potential energy. Alternatively, you could use the definition of Work=Force * Distance if you are given that information instead. For example, if you apply a 5 Newton force over 20 meters, 5N*20m=100J of work done which is all gained by the object being pushed on.
How do you convert electrical energy into potential energy?
You can use the electricity to pump water up into a high reservoir, where it then has mechanical potential energy. Or store it in a battery - chemical potential energy.
Is gasoline kinetic or potential energy?
It can be both, potential energy whilst in store, but kinetic energy when put to practical use.
Calculate the velocity of ball just before it hits the ground when dropped from a height of 6m?
Here are two different methods to solve this kind of problem. 1) Use one of the formulae for constant acceleration. In this case, vf2 = vi2 + 2as, where vf is the final velocity, vi is the initial velocity (zero in this case), a is the acceleration (9.8 meters / second2), and s is the distance. 2) Do an energy calculation, as follows: Calculate the potential energy at a height of 6 meters, with the formula PE = mgh. Since we can assume that the entire potential energy gets converted to kinetic energy just before the ball hits the ground, solve for velocity, in the kinetic energy formula.
