Answer:
39 m/s
Explanation:
Hi!
The equation of motion of the ball is:
Where y_0 is the initial horizontal position, which we will take as zero.
v_0y is the initial velocity and t is the time
To find the initial velocity we will set y(7.96s) = 0
You do a certain amount of work on an object initially at rest, and all the work goes into increasing the object’s speed. If you
1 answer:
Answer:
v_{f2} = √ 2 v_{f}
Explanation:
Work and kinetic energy are related by
W = ΔK
The formula for work is
W = F . d
The formula for kinetic energy is
K = ½ m v²
W = - K₀
Since the body starts from rest, the initial velocity is ro and therefore the kinetic energy is zero.
W = K_{f}
W = ½ m v_{f}²
v_{f} = √ 2W / m
If W = 2 W₀
v_{f2} = √ 2 (2W₀) / m
v_{f2} = √ 2 √2W₀ / m
v_{f2} = √ 2 v_{f}
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Answer:
d = <23, 33, 0> m , F_W = <0, -9.8, 0> , W = -323.4 J
Explanation:
We can solve this exercise using projectile launch ratios, for the x-axis the displacement is
x = vox t
Y Axis
y = t - ½ g t²
It's displacement is
d = x i ^ + y j ^ + z k ^
Substituting
d = (23 i ^ + 33 j ^ + 0) m
Using your notation
d = <23, 33, 0> m
The force of gravity is the weight of the body
W = m g
W = 1 9.8 = 9.8 N
In vector notation, in general the upward direction is positive
W = (0 i ^ - 9.8 j ^ + 0K ^) N
W = <0, -9.8, 0>
Work is defined
W = F. dy
W = F dy cos θ
In this case the force of gravity points downwards and the displacement points upwards, so the angle between the two is 180º
Cos 180 = -1
W = -F y
W = - 9.8 (33-0)
W = -323.4 J