1) The kinetic energy of an object is given by:
where m is the object's mass and v its speed.
By using this equation, we find the initial kinetic energy of the skateboarder:
and the final kinetic energy as well:
So, her change in kinetic energy is
2) The work-energy theorem states that the work done to increase the speed of an object is equal to the variation of kinetic energy of the object:
Therefore, the work done by the skateboarder is
Speed of wave is 8000 m/s.
Answer:
Explanation:
Speed is the measure of ratio of distance to time taken to cover that distance. In other words, speed is the measure of how fast the object can be move in a given time interval. So in this case, the wave is considered as object . And wave consists of wavelength in place of distance and frequency as reciprocal of time interval.
So speed of wave is calculated as the product of wavelength and frequency.
As the wavelength is given as 20 m and the frequency is given as 400 Hz, then the speed will be
Speed = wavelength × Frequency = 20 × 400
Speed of wave = 8000 m/s.
So speed of wave is 8000 m/s.
An inclined plane, just like all simple machines, makes work easier. I think it is a type of simple machines. Therefore, I think the best answer is A.
Answer: <u>Centrifugal Force </u>
Explanation:
The force that pulls out from the center on a body in circular motion is called centrifugal force and it increases with acceleration. Centrifugal force results in strong outward pull on your vehicle.
