Answer:Friction is a force that opposes the motion of objects; friction can cause objects to slow down. Air resistance is a type of friction. Air resistance causes moving objects to slow down. Different physical properties, such as the shape of an object, affect the air resistance on an object.
Explanation:
Answer:
3m
Explanation:
89.1 MHz means
89.1×10^6 cycles/second.
Electromagnetic radiation (including radio waves) travel at
3.0×10^8meters/second
Wavelength = Speed/Frequency
The wavelength of a
89.1MHz radio signal is
3.0×10^8/89.1x10^6
= 0.03x10^2
= 3meters
Acceleration = change in velocity / time
change in velocity = final velocity - initial velocity
because the object is slowing down, the acceleration will be negative.
acceleration = (4-34) / 60
acceleration = -30 / 60
acceleration = -0.5 m/s^2
answer : the train is accelerating at -0.5 m/s^2
This can be solve using snell's law. snell's law equation is :
N1 / N2 = sin a2 / sin a1
where N1 is the index of refraction of the air which is equal to 1
N2 is the index of refraction of the medium
a2 is the angle of refraction
a1 is the incident angle
subsitute the given values
1 / N2 = 0.173 / 0.217
N2 = 1 ( 0.217 / 0.173)
N2 = 1.25 is the index of refraction
