Overview
Answer and explain these 5 question.
1-An object moves with a constant speed of 16 m/s around a circle of radius 0.5 m.
- What is the time period of the motion?
- What is the magnitude of the centripetal acceleration of the ball?
- What is the direction of the centripetal acceleration?
- What is the angle between the circular velocity and acceleration at a given instant of time?
- How is the circular velocity different from the constant speed of the object moving in a circular path?
2-In a DVD player, the centripetal acceleration is measured to be 200 m/s2, at a point that is 0.02 m from the center of the disc.
- What is the rotating speed of the DVD?
- What is the centripetal acceleration at a point that is 0.06 m from the center of the disc?
- Is the rotating speed of the DVD different at different radial locations?
3- In a traditional wall mounted clock, the second hand makes one revolution in 60.00 s. The length of the second hand is found to be 6 cm.
- What is the speed of the end of the second hand?
- What will be the speed at a point midway on the second hand?
4-A nylon string is rated to withstand a force/tension of 100 N. A boy decided to play with this string to whirl a 0.8-kg object in a horizontal circle of radius 3.5 m.
- As the boy increases the speed of the object, up to which speed the string will remain intact?
- At that moment, what is the centripetal acceleration of the object?
- Suppose the boy decided to break the object in half (the new mass become half the original mass), and extend the string radius to 7 m using the same quality string (to withstand 100 N force). What changes will occur to the maximum circular velocity and centripetal acceleration?
5-A biker has a constant speed of 30.0 m/s as it passes over the top of a hill. The hill has a radius of curvature is 150 m. The mass of the bike and rider is 400 kg. Calculate the magnitudes of all the forces (e.g. centripetal force, gravitational force, normal forces etc) that act on the bike.