The speed of the brick dropped by the builder as it hits the ground is 17.32m/s.
Given the data in the question;
Since the brick was initially at rest before it was dropped,
- Initial Velocity;
- Height from which it has dropped;
- Gravitational field strength;
Final speed of brick as it hits the ground; 
<h3>Velocity</h3>
velocity is simply the same as the speed at which a particle or object moves. It is the rate of change of position of an object or particle with respect to time. As expressed in the Third Equation of Motion:
Where v is final velocity, u is initial velocity, h is its height or distance from ground and g is gravitational field strength.
To determine the speed of the brick as it hits the ground, we substitute our giving values into the expression above.
Therefore, the speed of the brick dropped by the builder as it hits the ground is 17.32m/s.
Learn more about equations of motion: brainly.com/question/18486505
-- pass the light through a lens
The path of the light is bent (refracted) to a new direction.
-- bounce the light off a shiny surface
The light is sent back (reflected) in the direction from which it arrived.
-- pass the light through a prism
The light is spread out according to the different wavelengths
that may be in it.
-- put something black in the light's path
The light is completely absorbed and is never seen again.
-- turn the light off
The source stops emitting light.
-- throw a towel over the lamp
The light is absorbed in the towel, and not seen outside of it.
Answer:
180,000
Explanation:
Frequency is a quantity that is measured in Hertz [Hz] and it represents the number of rotations per second.
A motor with a frequency of 50 Hz will rotate 50 times per second.
Since we don't want to know how many times it rotates per second, but per hour. The first step is to find how many seconds there are in an hour and then multiply that amount by 50.
Seconds in an hour:
there are 60 seconds per minute, and 60 minutes per hour, thus there are
60*60 = <u>3,600 seconds in an hour</u>
We know that the motor will rotate 50 times per second so to find the number of rotations in 1 hour = 3,600 seconds we multiply:
50*3,600 = 180,000 rotations
The correct statement is
Ultraviolet light has both a higher frequency and a higher radiant energy than visible light.
because ultraviolet light has wavelength smaller than the visible light hence has a greater frequency as compared to visible light. (frequency is inversely related to wavelength. hence smaller the wavelength , greater will be the frequency)
we also know that the radiant energy is directly proportional to the frequency. hence greater the frequency , greater will be the radiant energy.
Since the frequency is greater for ultraviolet light , it radiant energy is also greater
