ANSWER
EXPLANATION.
To write in scientific notation means , we write in form,
Where n is an integer and
The given number is,
We move the decimal point backward to obtain our k, the n here is 9, because we moved backward 9 times.
This implies that,
The correct answer is D
The frictional force required is 9000 N
Explanation:
In order to keep the car in the turn in circular motion without sliding, the frictional force must provide the centripetal force necessary for the circular motion.
Therefore, we can write:
where the term on the left is the frictional force while the term on the right is the centripetal force, and where:
m is the mass of the car
v is its speed
r is the radius of the curve
For the car in this turn, we have
m = 1000 kg
v = 30 m/s
(since the diameter is 0.20 km, the radius is half that value)
And substituting, we find
Learn more about friction:
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