Hey everyone! I really need help with this question, if you could explain how to do it and show the calculations also that would be great!! THANK YOU!
This is what I have to prove I know when answering (the actual question is below):
I can analyse, in qualitative and quantitative terms, the relationship between work and energy, using the work–energy theorem and the law of conservation of energy, and solve related problems in one and two dimensions.
Question:
A ball of mass m is thrown straight up into the air at a velocity of 4.1 m/s, from a height of 1.8 m.
a) Using energy analysis, determine its velocity at a height of 2.3 m.
b) Using energy analysis, what is the ball’s maximum height?
This is what I have to prove I know when answering (the actual question is below):
I can analyse, in qualitative and quantitative terms, the relationship between work and energy, using the work–energy theorem and the law of conservation of energy, and solve related problems in one and two dimensions.
Question:
A ball of mass m is thrown straight up into the air at a velocity of 4.1 m/s, from a height of 1.8 m.
a) Using energy analysis, determine its velocity at a height of 2.3 m.
b) Using energy analysis, what is the ball’s maximum height?
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a) set 1.8m as reference point.
Einitial = Efinal
Ek = Ek2 + Eg
1/2 mv^2 = 1/2 mv^2 + mgh
1/2 m(4.1^2) = 1/2 m v^2 + m (9.8)(2.3-1.8) mass cancels out
v = 2.65 m/s
b) at the maximum height, velocity = 0:
Ek = Eg
1/2 m(4.1^2) = m (9.8) (h) mass cancels out
h = 0.86m
maximum height = 0.86 + 1.8 = 2.66m
Einitial = Efinal
Ek = Ek2 + Eg
1/2 mv^2 = 1/2 mv^2 + mgh
1/2 m(4.1^2) = 1/2 m v^2 + m (9.8)(2.3-1.8) mass cancels out
v = 2.65 m/s
b) at the maximum height, velocity = 0:
Ek = Eg
1/2 m(4.1^2) = m (9.8) (h) mass cancels out
h = 0.86m
maximum height = 0.86 + 1.8 = 2.66m