Answer:
b.The frictional force and force exerted by the spring scale on the block, because they are a Newton's third-law pair.
Explanation:
Students connect a spring scale to a block on a rough horizontal surface. The students use the spring scale to measure the magnitude of the horizontal force needed to pull the block at a constant speed. Which of the following statements explains why two forces exerted between objects ar equal in magnitude?
a.A The gravitational and normal forces exerted on the block, because they are a Newton's third-law pair.
b.The frictional force and force exerted by the spring scale on the block, because they are a Newton's third-law pair.
c.The normal force and the frictional force exerted on the block, because objects always exert forces of equal magnitude on each other.
d.The frictional forces that the block and the surface exert on each other, because objects always exert forces of equal magnitude on each other.
solution \
the answer will be B
for a body to travel in a horizontal direction, it must be equal in direction to the frictional force which is in opposite direction to the force applied to move the block.
Also Newton's third law of motion must be obeyed , which states that action and reaction are equal and opposite
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The answer is C because the troposphere is part of earth's atmosphere while the photosphere is below the chromosphere. A corona is known as the aura around stars.
Answer: Taking into account sound is a wave, we can use the information of the displacement (generally given as a graph) to find the wavelength and frequency, then we can calculate the speed with the formula of the speed of a wave.
Explanation:
If we have the displacement graph of the sound wave, we can find its amplitude, its wavelength and period (which is the inverse of frequency).
Now, if we additionally have the frequency as data, we can use the equation of the speed of a wave:
Where:
is the speed of the sound wave
is the wavelength
is the frequency
In California, changing lanes in the middle of an intersection D. is legal.
Although it is legal, it's not necessarily the safest thing to do in an intersection.