It’s A because energy passes freely through the atmosphere and is absorbed by earths surface.
Frequency f =5×10^9Hz
Speed of radio waves=speed of light c =3×10^8m/s
Wavelength λ = c/f
= 3×10^8/5×10^9
= 0.06m
When the applied force increases to 5 N, the magnitude of the block's acceleration is 1.7 m/s².
<h3>
Frictional force between the block and the horizontal surface</h3>
The frictional force between the block and the horizontal surface is determined by applying Newton's law;
∑F = ma
F - Ff = ma
Ff = F - ma
Ff = 4 - 2(1.2)
Ff = 4 - 2.4
Ff = 1.6 N
When the applied force increases to 5 N, the magnitude of the block's acceleration is calculated as follows;
F - Ff = ma
5 - 1.6 = 2a
3.4 = 2a
a = 3.4/2
a = 1.7 m/s²
Thus, when the applied force increases to 5 N, the magnitude of the block's acceleration is 1.7 m/s².
Learn more about frictional force here: brainly.com/question/4618599
D.N(Newton) this is the S.I unit for force
As the balls continue to accelerate to the ground, the distance between them before the first ball hits the ground will increase.
<h3>What is acceleration?</h3>
Acceleration is defined as the rate change of velocity with time.
acceleration a = (Δv) / (Δt)
Two identical heavy balls are dropped from the top of the Leaning Tower of Pisa. The second ball is dropped 1 s after the first ball. The first ball start falling 1s earlier than the second ball. Thus, the acceleration for first ball will be greater than the second ball.
Thus, the distance between them before the first ball hits the ground will increase.
Learn more about acceleration.
brainly.com/question/12550364
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