In the presence of air resistance, a watermelon is launched into the air with 100 j of kinetic energy.
Its kinetic energy is less than 100 J when it reaches its starting point. Its kinetic energy decreases as it encounters air resistance and returns to its starting point. In actuality, some of the energy has been lost because of air resistance. Since we use the ball's original height as a point of reference, there is no potential energy when the ball is in its initial state of motion, and K is its kinetic energy. This total energy is conserved if there is no air resistance, therefore when the ball returns to its starting position, its kinetic energy will remain at 100.
Learn more kinetic energy about here:
brainly.com/question/12669551
#SPJ4
Answer:
v = 34.128 km/hr
Explanation:
Given that,
The initial speed of a truck, u = 0
Acceleration of the truck, a = 0.3 m/s²
Distance moved, d = 150 m
Let the final speed of the truck is v. Using third equation of motion i.e.

Put all the values,

or
v = 34.128 km/h
So, the final speed of the truck is equal to 34.128 km/h.
I believe the answer is A
B. the sum of the protons and the neutrons in one atom of the element
Potassium is the 19th element so it is B