The setting sun is actually visible after it has dropped below the horizon due to the bending of light waves entering the atmosp
2 answers:
You might be interested in
The final velocity is +15.0 m/s
Explanation:
The motion of the cart is a uniformly accelerated motion (=at constant acceleration), therefore we can use the following suvat equation:
where
v is the velocity at time t
u is the initial velocity
a is the acceleration
t is the time
For the cart in this problem, we have:
u = +3.0 m/s (initial velocity)
(acceleration)
t = 8.0 s (time)
Substituting, we find the final velocity:
Learn more about accelerated motion:
#LearnwithBrainly
Answer:
a) W = 180.87 J , b) ΔU = -180.87 J , c) ΔU = -180.87 J
Explanation:
a) Work is defined as
W = F .ds
Where bold indicates vectors, we can write the scalar product
W = F s cos θ
Where the angle is between force and displacement.
The force of gravity is the weight of the body, which is directed downwards and the displacement thickens the tip of the cliff at the bottom, so that it is directed downwards, therefore the angle is zero degrees
W = y
W = m g y
For this problem we must fix a reference system, from the statement it is established that the system is placed at the base of the cliff, so that final height is zero and the initial height (y₀ = 7.69m)
W = 2.40 9.8 (7.69-0)
W = 180.87 J
b) The potential energy is
U = mg y
The change in potential energy,
ΔU = - U₀
ΔU = mg (- y₀)
ΔU = 2.4 9.8 (0 -7.69)
ΔU = -180.87 J
c) in this case we change the reference system to the height of the cliffs, for this configuration
y₀ = 0
= -7.69 m
ΔU = 2.4 9.8 (-7.69 -0)
ΔU = -180.87 J