Concept explainers
(a)
To Find:The normal force.
(a)
Answer to Problem 94P
Explanation of Solution
Given Information:
Radius of the curve is
Banking angle is
Mass of car is
Speed of the car is
Formula Used:
The acceleration of the car along x- axis is the centripetal acceleration, that is,
Here,
Calculation:
The free-body diagram for the car on the curved road is as follows
In the free body diagram shown below, the normal force and the static friction force, both contribute to the centripetal force according to the situation described in this problem.
The speed of the car is
The net force on the x -axis is
Substitute
Multiply the equation
The net force on the y-axis is,
Multiply the above equation with
Add the equations
Rearrange the above equation for the normal force
Substitute
Conclusion:
The normal force exerts on the car is
(b)
To Find:The frictional force exerted by the pavement on the tires.
(b)
Answer to Problem 94P
The frictional force exerted by the pavement on the tires is
Explanation of Solution
Given Information:
Radius of the curve is
Banking angle is
Mass of car is
Speed of the car is
Formula Used:
The net force along the y-axis is
Calculation:
Rearrange the above equation:
Substitute
Conclusion:
The frictional force exerted by the pavement on the tires is
(c)
To Find:The coefficient of the static frictional force.
(c)
Answer to Problem 94P
Explanation of Solution
Given Information:
Radius of the curve is
Banking angle is
Mass of car is
Speed of the car is
Formula Used:
The equation for the frictional force is
Here,
Calculation:
Rearrange the above equation for
Substitute
Conclusion:
The coefficient of the minimum static frictional force is
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Chapter 5 Solutions
Physics for Scientists and Engineers
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