B. I think is the correct answer
The dotted path is the path of the ball. it reaches it's maximum height at the top where vertical, y-velocity = 0
The initial y-velocity = 19sin(70°)
initial y-velocity = 17.85 m/s
Use one of the kinematic equations with velocity and time. No displacement because we don't want to worry about figuring that out.
v = u - gt
0 = 17.85 - 9.8t
-17.85 = -9.8t
17.85/9.8 = t
1.82 sec = t
Answer:
W = 157.5kJ
Explanation:
Assuming it moves the container at constant speed, the work done by the crane will be equal to the variation of the potential gratitational energy on the container:
where h2= -8m and h1=0m
Wc = 157.5kJ
Helium atom, in other words, it consistis of a particle having four protons and two neutrons.
