6. A pottery wheel with a diameter of 90cm is initially at rest. After the motor is turned on, it takes 20.0s for the pottery wheel to reach an angular speed of 50rpm. a) What is the angular acceleration of the pottery wheel during those 20 seconds? b) By how much does the pottery wheel rotate during those 20 seconds? The pottery wheel is now rotating with a constant angular speed of 50rpm. c) If a piece of clay is stuck to the pottery wheel at a distance of 40cm away from the center, what is the magnitude of the acceleration of the piece of clay as it goes around? d) In what direction is the acceleration of the piece of clay as it goes around in cirrcles?

Angular frequency vs angular velocity? Consider the diagram of UCM (and its y-motion) shown below. How do the magnitudes of the angular frequency and angular velocity compare in this motion? +A wt wt TT/2 TT 31/2 2TT -A The magnitude of the angular frequency is greater than the magnitude of the angular velocity. The magnitude of the angular frequency is less than the magnitude of the angular velocity. The magnitude of the angular frequency is equal to the magnitude of the angular velocity.

Which of the following is not an example of an object:  a. A car is rounding a bend at a constant speed. b. A merry-go-round increases from rest to a constant rotational speed.  c. A pendulum swings back and forth. d. A bowling ball rolls down a bowling alley.

4. A pinball of mass M and radius R is pushed against a spring of spring constant k. The spring is compressed a distance D and the pinball machine ramp is inclined at an angle 0. The spring is then released. The pinball is a solid metal sphere that rolls without slipping. a. Determine the speed of the pinball as it leaves the spring. Hint: the spring force is not constant so you cannot use constant acceleration kinematics. Use conservation of mechanical energy instead. b. What is the distance that the pinball would go up the ramp before coming back down?

1. A 97 g ball bobbing up and down on the ocean as the waves roll by has a vertical position that can be described as a function of time by x(t) = cos(10t). What is the force on the ball at a time of 4.6 seconds? Note: The argument of the cosine function is in radians. Hint: Don't forget the sign of the force. F = 6.74 X√ N

2. Determine the moment of inertia of the shaded area with respect to the y axis. 8 mm- 1: 12 mm y 24 mm 12 mm -24 mm + 6 mm 24 mm 24 mm. 6 mm

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NOTE: The answer of 85.715 rpm was given to me and was incorrect. What is the correct answer?

Constants A grinding wheel 0.21 m in diameter rotates at 2500 rpm Part B What is the linear speed of a point on the edge of the grinding wheel? Express your answer to two significant figures and include the appropriate units. HÀ ? 35.60 V = S Submit Previous Answers Request Answer X Incorrect; Try Again; 4 attempts remaining Part C What is the acceleration of a point on the edge of the grinding wheel? Express your answer to two significant figures and include the appropriate units. HẢ ? Value Units AR =

1. A point on the outer rim of a hollow disk (I = mr2) with radius r and mass m rotates with a constant angular speed of ω. How far will the point travel (in meters) in 1 minute of rotation? Let w=11.5 rad/s and r=0.78m a. how many revolutions will the point experience during this time? b. What net torque is necessary to stop the disk in time t? Let t=7 sec and m =14kg