A car travels in a circle whose radius is 31 m, with a speed of 19 m/s.
(1) What is the magnitude of the car's acceleration?
_____ m/s2
(2) What is the nature (origin) of the horizontal force on the car? (What is exerting the force?)
The force causing the car to turn is:
CHOOSE ONE:
a) the Coriolis force from the car's non-inertial
reference frame.
b) the force of friction between the car's tires and
the road.
c) the gravitational force between the earth and the
car.
d) the mechanical force provided by the car's
engine.
To find the magnitude of the car's acceleration, we need to use the formula for centripetal acceleration:
acceleration = (velocity^2) / radius
Given that the velocity of the car is 19 m/s and the radius of the circle is 31 m, we can plug these values into the formula to find the answer.
Acceleration = (19^2) / 31
= 361 / 31
≈ 11.645 m/s^2
Therefore, the magnitude of the car's acceleration is approximately 11.645 m/s^2.
Now, to determine the nature or origin of the horizontal force on the car, we can analyze the given options.
a) The Coriolis force from the car's non-inertial reference frame is not applicable in this scenario. The Coriolis force is a force that appears due to the rotation or acceleration of objects in a non-inertial reference frame, but in this case, we are observing the car from a fixed reference frame.
b) The force of friction between the car's tires and the road is the correct answer. This frictional force acts horizontally to provide the required centripetal force for the car to turn in a circle. It enables the tires to grip the road and prevent the car from sliding off the circular path.
c) The gravitational force between the earth and the car is not relevant in this scenario. While gravity does act on the car, it is not responsible for the car turning in a circle.
d) The mechanical force provided by the car's engine is also not directly related to the car turning in a circle. The engine produces a forward force to overcome friction and propel the car, but it does not directly influence the car's circular motion.
Therefore, the correct answer is (b) the force of friction between the car's tires and the road.