<h2>
Its velocity when it crosses the finish line is 117.65 m/s</h2>
Explanation:
We have equation of motion s = ut + 0.5 at²
Initial velocity, u = 0 m/s
Acceleration, a = ?
Time, t = 6.8 s
Displacement, s = 1/4 mi = 400 meters
Substituting
s = ut + 0.5 at²
400 = 0 x 6.8 + 0.5 x a x 6.8²
a = 17.30 m/s²
Now we have equation of motion v = u + at
Initial velocity, u = 0 m/s
Final velocity, v = ?
Time, t = 6.8 s
Acceleration, a = 17.30 m/s²
Substituting
v = u + at
v = 0 + 17.30 x 6.8
v = 117.65 m/s
Its velocity when it crosses the finish line is 117.65 m/s
Correct answer is letter B. sandstone
The statement: "secondary evidence is the basis for drawing scientific conclusions" is definitely false. Secondary evidence is the body of information obtained to prove the existence of unknown or missing primary evidence. In drawing scientific conclusions, primary evidence is needed.
Magnetic stripes on the sea floor
Explanation:
The observation of magnetic stripes patterns at the region of the Mid-Atlantic Ridge galvanized the evidence that sea floor spreading has been on for several millions of years.
- Geomagnetic field of the earth is similar to that of bar magnet having the north and south pole.
- It originates from the movement of iron-nickel within the outer core.
- This geomagnetic field causes the magnetization of magnetic minerals in rock.
- When freshly formed magma is brought to the surface at the mid oceanic ridge area, the prevailing magnetic field causes the magnetic minerals in the magma to cool in such a way that they align their domains to that of the field.
- The magnetic field of the earth can reverse and take different geometry. Sometimes, its intensity is very strong and at other times it is weak.
- The magnetic minerals in melts bear these records.
- As new materials are brought up, they get magnetized.
Learn more:
Sea floor spreading brainly.com/question/9912731
#learnwithBrainly
A rotational force, also known as a torque, depends upon the force and where that force is applied; torque = lever arm x force. The lever arm is the perpendicular distance from the force to the axis of rotation.
