Final answer:
To find the velocity of the ball at different positions along its swing, we can use the principle of conservation of energy. At position B, when the string is vertically down, all of the potential energy has been converted into kinetic energy. By resolving the components of the force due to gravity, we can find the velocities at angles of 20° and 10°. The tension in the string at position B can be found using the equation tension = weight.
Step-by-step explanation:
To solve this problem, we can use the principle of conservation of energy. At position A (the highest point), the ball has potential energy, and as it swings down to position B (the lowest point), this potential energy is converted into kinetic energy. We can use this principle to find the speed of the ball at different positions along its swing.
a) When the string is vertically down, at position B, all of the potential energy has been converted into kinetic energy. So using the equation ke = (1/2)mv^2, where m is the mass of the ball (0.2 kg), and v is the velocity, we can solve for v. b) For angles of 20° and 10°, we need to consider the component of the force due to gravity acting in the direction of the motion, as well as the component perpendicular to the motion. By resolving these components and using the equation ke = (1/2)mv^2, we can find the velocities.
b) The tension in the string at position B can be found using the equation tension = weight, where weight = mass * gravity. So we have tension = 0.2 kg * 9.8 m/s^2.