General
In terms of angular momentum, it can be measured in in two units ____ and ______
What is m/s and rev/s
What quantity describes the ability of a force to rotate an object
What is torque
What is the direction of the acceleration of an object moving in a circle?
What is toward the center
Angular momentum = Mass x Velocity x ____
What is radius
What term describes how distance changes in a specific amount of time and what are the units for this term?
What is velocity and m/s
If you can only apply 100N of force on a wrench. what could you do to increase torque?
Increase lever arm size.
This refers to the perpendicular distance from the rotational axis to the line along which the force acts
What is the lever arm
What is the direction of the net force of an object moving in a circle?
What is toward the center
True/False: Angular momentum will remain the same unless acted upon by an external net torque
What is true
What is the term to describe how velocity changes in a certain amount of time and what are the units for this term?
What is acceleration and m/s^2?
True or False: Rotational inertia is increased when the mass is distributed away from the center, which means the object will move faster.
What is False (Rotational Inertia is increased, but this would make the object would move slower, NOT faster)
A student pushes with a force of 50N on the middle of a door to open it. What minimum force must be applied at the edge of the door in order for the door to open?
What is 25N
If a ball is swung in a circle by a string and that string breaks, what force is needed to keep the ball in motion? Which of Newton's laws supports your answer?
What is no force is needed. Newton's first law.
Why does a ice skater spin faster when they bring their arms inward?
What is they decrease their radius, thereby increasing their rotational speed
What are the equations for potential energy and kinetic energy?
What is PE = mgh and KE = 1/2mv^2
It is easier to swing a baseball bat when it is held closer to the more massive end (when it's choked up) because _____
What is the rotational inertia is decreased
A student pushes with a force of 50N on one side of the door. another student pushes on the otherside of the door near the hinge. What is the minimum force must be applied to the hinged side of the door in order for him to open it?
What is the door cannot be opened by a force at the hinge location
A 90kg person rides a spinning amusement park ride that has a radius of 11.5m. If the person's tangential speed is 13.2 m/s, what is the magnitude of the centripetal force acting on the person?
What is 1.36 x 10^3 N
If a 0.03kg mass is placed at the 15cm mark where should a 0.08kg mass be placed to balance the system? (fulcrum would be at the 50cm mark)
What is 55.6cm mark.
What is the equation for the conservation of energy? (yes...the really long one)
What is mghi + 1/2mvi^2 = mghf + 1/2mvf^2
Consider two axes of rotation for a pencil: axis through the lenght of the pencil and an axis of rotation in the middle of the pencil. What has the higher rotational inertia?
What is: Axis through the middle of the pencil.
Find the magnitude of the torque produced by a 3.0N force applied to a a door at a perpendicular distance of 0.25, from the hinge.
What is 0.75Nm
What makes a passenger in a turning car slide toward the door of the car?
What is the passenger's inertia keeps the person moving in the same direction that the car was originally moving before it turned (the person's inertia is working against the centripetal force acting on the car).
A person with a mass of 85kg is sitting on a rotating platform with a radius of 1.5m and is spinning with a tangential speed of 5m/s. If the person speed doubles and all else remains the same, what is the person's angular momentum?
What is 1,275 kgm^2/s
What is the work done if a force of 75N is applied to a box at an angle degrees above the horizontal and the box moves 5m along the floor?
W=Fxd
What is 375 Nm