Answer:

Given:
Mass (m) = 6 kg
Speed (v) = 4 m/s
To Find:
Kinetic energy (KE)
Explanation:
Formula:

Substituting values of m & v in the equation:




I assume you mean that the car's motor is not running ... the car is just
sitting there.
If that's so, then the car's mechanical energy is just like the mechanical
energy of any other object. It has potential energy if it's in a high place
from which it can roll or fall, and it has kinetic energy if it's moving.
-- If you make the car move by pushing it, then you gave it kinetic energy
that it didn't have while it was just sitting there.
-- If it's already moving slowly, and you're able to make it move faster by
pushing, then you increased its kinetic energy.
-- If you're able to push it up a hill, no matter how small the hill is but just
to any higher place, then you gave it more gravitational potential energy
than it had before you came along.
In all of these cases, if you exert a force and keep exerting it through some
distance while the car moves, then you have done "work", which is just
another name for mechanical energy, and your work adds to the mechanical
energy of the car.
But if you didn't move the car, then no matter how hard you pushed, no work
was done, and the car's mechanical energy didn't change.
The acceleration of the body is provided by the tension in the rope.
<h3>What is centripetal acceleration?</h3>
The centripetal acceleration is given by a = v^2/r. v = velocity of the body, r = radius
a = (8.40 m/s)^2/(8.50 m)
a = 8.3 m/s^2
The tension in the rope is the force that provides the centripetal force in the rope.
Learn more of centripetal acceleration:brainly.com/question/14465119
#SPJ1
<h3>Answer:</h3>
C) 500,000 J
<h3>Explanation:</h3>
The change in potential energy is ...
Mgh = (1000 kg)(9.8 m/s^2)(50 m) = 490,000 J . . . . roughly matches C
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<em>Comments on the problem</em>
The efficiency of the motor is unknown, so the amount of energy spent as heat is unknown.
In the equation above, we have used M for mass, and m for meters. The acceleration due to gravity is approximately 9.8 m/s^2, varying depending on location and height above the Earth. The "standard" value for g will add a few more joules to this value, but will not make it 500,000.