A 0.20-kg ball on a string is whirled on a vertical circle at a constant speed. When the ball is at the three o'clock position, the string tension is 16 N. Find the tensions in the string when the ball is at twelve o'clock and at the six o'clock positions.

How can I find the v and the r for 3 o'clock.

To find the tensions in the string when the ball is at twelve o'clock and six o'clock positions, we can use the principles of centripetal force.

The centripetal force is the force that keeps an object moving in a circular path. In this case, the tension in the string provides the centripetal force that keeps the ball moving in a circle.

When the ball is at the three o'clock position, the tension in the string is given as 16 N. This is the force required to keep the ball moving in a circle at that specific position.

To find the tension in the string when the ball is at twelve o'clock and six o'clock positions, we need to consider the forces acting on the ball at those positions. At the topmost point (twelve o'clock position), the tension in the string will be the sum of the weight of the ball (mg) and the centripetal force necessary for circular motion. At the bottommost point (six o'clock position), the tension in the string will be the difference between the weight of the ball (mg) and the centripetal force necessary for circular motion.

The weight of the ball can be calculated using the formula: weight = mass x acceleration due to gravity (weight = mg), where "m" denotes mass and "g" denotes acceleration due to gravity.

Given the mass of the ball (0.20 kg), we can calculate the weight:
weight = 0.20 kg x 9.8 m/s^2 = 1.96 N

Now, we can calculate the tension in the string at twelve o'clock and six o'clock positions.

At twelve o'clock position:
Tension = weight + Centripetal force
Tension = 1.96 N + Centripetal force

At six o'clock position:
Tension = weight - Centripetal force
Tension = 1.96 N - Centripetal force

To determine the centripetal force, we need to consider the velocity of the ball at each position. Since the ball is moving at a constant speed, the magnitude of the velocity will be the same at all points on the circle. We can use the following formula to calculate the centripetal force:

Centripetal force = (mass x velocity^2) / radius

Since the radius is not given in the question, we cannot calculate an exact value for the tension in the string at twelve o'clock and six o'clock positions without knowing the radius or the velocity of the ball. Therefore, we need additional information to solve the problem.

at three oclock, Tension= mv^2/r

then at 12 oclock,
tension= mv^2/r-mg
and at six...
tension= mv^2/r + mg