Answer:
coasting down hill on a bicycle
Explanation:
Coasting down the hill on a bicycle is a typical example of how kinetic energy is being transformed to potential energy in a system.
Kinetic energy is the energy due to the motion of a body, it can be derived using the expression below;
K.E = 
m v²
Potential energy is the energy due to the position of a body. It can be derived using;
P.E = mgh
m is the mass
v is the velocity
g is the acceleration due to gravity
h is the height
Now, at the top of the hill, the potential energy is at the maximum. As the bicycle coasts down the potential energy is converted to kinetic energy.
Some work will be done on friction between wheels and road but it is negligible compared to work done on friction on breaks.
W = Ek = (m*v^2)/2 = 2000*22^2/2 = 1000*22^2 = 484KJ
Because car is not changing its potential energy, there is no work to be done on while changing it which means that all goes on changing kinetic energy (energy of motion)
Answer:
Part a)
Part b)
Explanation:
Part a)
As we know that orbital velocity at certain height from the surface of Earth is given as
here we know that
now we have
Part b)
When a loose rivet is moving in same orbit but at 90 degree with the previous orbit path then in that case the relative speed of the rivet with respect to the satellite is given as
Answer: No, The energy will remain the same
Explanation: Doubling the mass and leaving the amplitude unchanged won't have any effect on the total energy of the system.
At maximum displacement, E=0.5kA^2
Where E = total energy
K = spring constant
A = Amplitude
From the formula above : Total Energy is independent of mass,. Therefore, total energy won't be affected by Doubling the mass value of the object.
Also when the object is at a displacement 'x' from its equilibrium position.
E = Potential Energy(P.E) + Kinetic Energy(K.E)
P.E = 0.5kx^2
Where x = displacement from equilibrium position
E = Total Energy
K. E= E-0.5kx^2
From the relation above, total energy is independent of its mass and therefore has no effect on the total energy.
Answer: the true statement form the given statements is “the athletes is not doing any work because he does not move weight”
