A uniform disk can rotate around its center like a merry-go-round as shown in figure. The disk has a radius of 10 cm and a mass of 300 grams. Starting from rest, the disk rotates to an angular
velocity of 300 rad/s, counterclockwise, in 1 = 2.5 seconds, due to four forces that are applied to
the disk as indicated in figure.
a Calculate the moment of inertia of the disk
b. What is the magnitude and direction of angular acceleration of the disk?
c. Using Newton's second law for rotation determine the magnitude of unknown force F4
F1 = 2 N
F2=3N
45N
5 cm 5 cm
F=?
F3 = 4N

According to newton's second law, when the same force is applied to two objects of different masses, a the object with greater mass will experience a great acceleration, and the object with less mass will experience an even greater acceleration, b. the object with greater mass will experience a smaller acceleration, and the object with less mass will experience a greater acceleration, c. the object with greater mass will experience a greater acceleration, and the object with less mass will experience a smaller acceleration, d. the object with greater mass will experience a small acceleration, and the object with less mass will experience an even smaller acceleration.

In the nineteenth century, gregor mendel first determined some basic rules of genetics that have been observed throughout all types of life. no observations have disproved these basic rules of genetics. charles darwin developed the idea of biological evolution around the same time, but he was unaware of mendel’s discoveries in genetics. over a century later, darwin’s idea of evolution was modified in order to incorporate mendel’s rules of genetics along with the other evidence that darwin had used. what is most likely the relationship between mendel’s rules of genetics and darwin’s idea of biological evolution? a.)mendel’s genetics states laws that are now part of the theory of biological evolution. b.)biological evolution states laws that are part of mendel’s theory of genetics. c.)mendel’s genetics replaced darwin’s entire concept of biological evolution. d.)biological evolution is a law that explains why all genetics exist.

Review multiple-concept example 7 in this chapter as an aid in solving this problem. in a fast-pitch softball game the pitcher is impressive to watch, as she delivers a pitch by rapidly whirling her arm around so that the ball in her hand moves in a circle. in one instance, the radius of the circle is 0.626 m. at one point on this circle, the ball has an angular acceleration of 66.1 rad/s2 and an angular speed of 12.6 rad/s. (a) find the magnitude of the total acceleration (centripetal plus tangential) of the ball. (b) determine the angle of the total acceleration relative to the radial direction.