Answer:
B
Explanation:
Conduction is transferred from one area to another. Conduction can occur within material or between materials that are in thermal contact.
Answer:
3) Ep = 13243.5[J]
4) v = 17.15 [m/s]
Explanation:
3) In order to solve this problem, we must use the principle of energy conservation. That is, the energy will be transformed from potential energy to kinetic energy. We can calculate the potential energy with the mass and height data, as shown below.
m = mass = 90 [kg]
h = elevation = 15 [m]
Potential energy is defined as the product of mass by gravity by height.
This energy will be transformed into kinetic energy.
Ek = 13243.5 [J]
4) The velocity can be determined by defining the kinetic energy, as shown below.
Answer:
The correct option is:
B) Kinetic Energy
Explanation:
We know that if a body is placed at a certain height, it possesses Potential Energy, which is represented by 'mgh'. In this case, when the skydiver is present in the plane, before jumping, he has potential energy as he is at height 'h'.
As Kinetic energy is given as '(1/2)mv²' dependent on velocity of the object, when the skydiver jumps of the plane, his height starts decreasing, which decreases his Potential Energy. As energy can neither be created or destroyed, but is converted to one form or another, all this Potential energy starts to convert into Kinetic energy. As Potential Energy decreases with distance, Kinetic energy increases. Hence, line B represents Kinetic Energy.
Answer:
d) The total mechanical energy is constant.
Explanation:
The total mechanical energy of a pendulum is given by:
where
KE is the kinetic energy (the energy of motion), given by
where
m is the mass of the pendulum
v is its speed
PE is the potential energy of the pendulum (the energy due to its position), given by
where
g is the acceleration due to gravity
h is the height of the pendulum relative to the ground
In absence of air resistance, the total mechanical energy of the pendulum is constant. This means that there is a continuous conversion of energy between kinetic and potential. In particular:
- When the pendulum is at its highest position (maximum displacement), the potential energy is maximum while the kinetic energy is minimum)
- When the pendulum crosses its equilibrium position, the kinetic energy is maximum (maximum speed) while the potential energy is minimum