Answer:
The ball will have a kinetic energy of 0.615 Joules.
Explanation:
Use the kinetic energy formula
The kinetic energy at the moment of leaving the hand will be 0.615 Joules. (From there on, as it ball is traveling upwards, this energy will be gradually traded off with potential energy until the ball's velocity becomes zero at the apex of the flight)
maximum allowed value of the speed in roller coaster is given as
now from kinematics we can say
here initial speed will be
acceleration is due to gravity
now we can use this to find the height
so maximum allowed height will be 20.4 m
Answer:
The work done by the force is 820.745 joules.
Explanation:
Let suppose that changes in potential energy can be neglected. According to the Work-Energy Theorem, an external conservative force generates a change in the state of motion of the object, that is a change in kinetic energy. This phenomenon is describe by the following mathematical model:
Where:
- Work done by the external force, measured in joules.
,
- Translational potential energy, measured in joules.
The work done by the external force is now cleared within:
After using the definition of translational kinetic energy, the previous expression is now expanded as a function of mass and initial and final speeds of the object:
Where:
- Mass of the object, measured in kilograms.
,
- Initial and final speeds of the object, measured in meters per second.
Now, each speed is the magnitude of respective velocity vector:
Initial velocity
Final velocity
Finally, if ,
and
, then the work done by the force is:
The work done by the force is 820.745 joules.