Answer: hydroelectric dams
Explanation: Enormous energy is stored in water held back by hydroelectric dams. The energy is transformed into (a form of kinetic energy) as it falls across the dam. The falling water strikes the blades of a turbine and makes them spin, and the then turns the shaft of a generator.
Answer: a) electromagnetic waves
Explanation:
An electromagnetic wave begins when an electrically charged particle vibrates. This causes a vibrating electric field, which in turn creates a vibrating magnetic field. The two vibrating fields together form an electromagnetic wave.
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<h2>
Answer:</h2>
(a) 10N
<h2>
Explanation:</h2>
The sketch of the two cases has been attached to this response.
<em>Case 1: The box is pushed by a horizontal force F making it to move with constant velocity.</em>
In this case, a frictional force 
is opposing the movement of the box. As shown in the diagram, it can be deduced from Newton's law of motion that;
∑F = ma -------------------(i)
Where;
∑F = effective force acting on the object (box)
m = mass of the object
a = acceleration of the object
∑F = F -
m = 50kg
a = 0 [At constant velocity, acceleration is zero]
<em>Substitute these values into equation (i) as follows;</em>
F - = m x a
F - = 50 x 0
F - = 0
F = -------------------(ii)
<em>Case 2: The box is pushed by a horizontal force 1.5F making it to move with a constant velocity of 0.1m/s²</em>
In this case, the same frictional force is opposing the movement of the box.
∑F = 1.5F -
m = 50kg
a = 0.1m/s²
<em>Substitute these values into equation (i) as follows;</em>
1.5F - = m x a
1.5F - = 50 x 0.1
1.5F - = 5 ---------------------(iii)
<em>Substitute </em><em> = F from equation (ii) into equation (iii) as follows;</em>
1.5F - F = 5
0.5F = 5
F = 5 / 0.5
F = 10N
Therefore, the value of F is 10N
<em />
Answer:
A) The ball hits the ground 74.45 m far from the hitting position.
B) Maximum height of the ball = 18.57 m
Explanation:
There are two types of motion in this horizontal and vertical motion.
We have velocity = 27 m/s at 45° above the horizontal
Horizontal velocity = 27cos45 = 19.09 m/s
Vertical velocity = 27sin45 = 19.09 m/s
Time to reach maximum height,
v = u + at
0 = 19.09 - 9.81 t
t = 1.95 s
So total time of flight = 2 x 1.95 = 3.90 s
A) So the ball travels at 19.09 m/s for 3.90 seconds.
Horizontal distance traveled = 19.09 x 3.90 = 74.45 m
So the ball hits the ground 74.45 m far from the hitting position.
B) We have vertical displacement
S = ut + 0.5 at²
H = 19.09 x 1.95 - 0.5 x 9.81 x 1.95² = 18.57 m
Maximum height of the ball = 18.57 m
Although the video is not found here, the sentence makes reference to the transmission spectrum of colored filters.
<h3>What is the transmission spectrum?</h3>
The transmission spectrum indicates the light portion having a given wavelength that can be passed through a filter.
This spectrum (transmission spectrum) depends on the physical separation of the particles that form the filter.
In conclusion, although the video is not found here, the sentence makes reference to the transmission spectrum of colored filters.
Learn more about the transmission spectrum here:
brainly.com/question/1287536
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