Answer:
1. The elephant has more kinetic energy at this speed and mass. It has 4,500 J more KE.
2. The elephant would have to go at a speed of 2.5 m/s to reach the same KE as the cheetah.
Explanation:
You would use the formula KE=1/2mv^2.
This formula would be filled in and completed twice, once for the elephant and once for the cheetah.
Cheetah:
KE = 1/2 (40) (25) ^2
KE = 12,500 J
Elephant:
KE = 1/2 (4,000) (2) ^2
KE = 8,000 J
This shows that the cheetah has more KE.
Then you would subtract the elephants amount of J from the cheetahs to find the difference.
Difference = 12,500 J - 8,000 J
Difference = 4,500 J
I hoped this helped with the first part :)
For the second part:
To find the speed the elephant would have to run you would fill in and complete the equation once more with different distance results.
KE = 1/2 (4,000) (2.5) ^2
KE= 12,500 J
Answer:
-6112.26 J
Explanation:
The initial kinetic energy,
is given by
} where m is the mass of a body and
is the initial velocity
The final kinetic energy,
is given by
where
is the final velocity
Change in kinetic energy,
is given by

Since the skater finally comes to rest, the final velocity is zero. Substituting 0 for
and 12.6 m/s for
and 77 Kg for m we obtain

From work energy theorem, work done by a force is equal to the change in kinetic energy hence for this case work done equals <u>-6112.26 J</u>
Explanation:
Geocentric model said that the Earth is at the center of the universe and everything revolves around it. It was considered to be stationary. Galileo proved this model incorrect with the help of his astronomical observations. Some of the key observation that he used to support the heliocentric model were:
1. He proposed the theory that the tides on the Earth occur because of its motion.
2. He observed the phases of the Venus which meant that the Venus revolved around the Sun and not the Earth.
3. He observed other planets and thus noted that they also move around the Sun and not Earth.
4. He discovered the Moons of other planets.
Francium is the most reactive alkali metal
Answer:
A wave is a disturbance that carries energy from one place to another.
Explanation: