Answer:
Explanation:
Given that,
Height of the bridge is 20m
Initial before he throws the rock
The height is hi = 20 m
Then, final height hitting the water
hf = 0 m
Initial speed the rock is throw
Vi = 15m/s
The final speed at which the rock hits the water
Vf = 24.8 m/s
Using conservation of energy given by the question hint
Ki + Ui = Kf + Uf
Where
Ki is initial kinetic energy
Ui is initial potential energy
Kf is final kinetic energy
Uf is final potential energy
Then,
Ki + Ui = Kf + Uf
Where
Ei = Ki + Ui
Where Ei is initial energy
Ei = ½mVi² + m•g•hi
Ei = ½m × 15² + m × 9.8 × 20
Ei = 112.5m + 196m
Ei = 308.5m J
Now,
Ef = Kf + Uf
Ef = ½mVf² + m•g•hf
Ef = ½m × 24.8² + m × 9.8 × 0
Ef = 307.52m + 0
Ef = 307.52m J
Since Ef ≈ Ei, then the rock thrown from the tip of a bridge is independent of the direction of throw
Answer:
θ = 14.45º = 0.252 rad
Explanation:
The expression that describes the phenomenon of diffraction is
a sin θ = m λ
Where a is the width of the exit opening in this case the width of the door, Lam is the wavelength, m the diffraction order for destructive interference,
Let's use the relationship between the speed of the wave is the producer of its frequency by the wavelength
v = λ f
λ = v / f
λ = 344/1220
λ = 0.282 m
sin θ = m λ / a
For the first destructive interference m = 1
sin θ = 1 0.282 /1.13
sin θ = 0.24956
θ = sin-1 (0.24956)
θ = 14.45º
We pass radians
θ = 14.45 (pi rad / 180º) = 0.252 rad
A ball held over a person's head | a ball rolling on the floor is an example of an object that has potential energy followed by an object that has kinetic energy.
<h3>What is Kinetic energy?</h3>
This is the type of energy possessed by a body by virtue of its motion or movement.
The rolling ball therefore has kinetic energy while a ball being held over a person's head has potential energy which is the energy possessed by a body by virtue of its position.
Read more about Kinetic energy here brainly.com/question/8101588
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Lightning is an electric current. Within a thundercloud way up in the sky, many small bits of ice (frozen raindrops) bump into each other as they move around in the air. All of those collisions create an electric charge. After a while, the whole cloud fills up with electrical charger
True because it has "falling" ability
