Which is a correct description of the object's motion? The object is moving at a constant velocity. Then it slows down and stops. The object rolls along a flat surface. It then rolls down a hill, and finally stops. The object moves along a flat surface. Then it rolls down a hill, and keeps goin The object does not move at first. Then it rolls down a hill, and keeps going. The object does not move at first. Then it moves at a constant velocity, and st

You're out in space, on a rotating wheel-shaped space station of radius 1426 m. You feel planted firmly on the floor due to artificial gravity. The gravity you experience is Earth-normal, that is, g = 9.81 m/s^2. How fast is the space station rotating in order to produce this much artificial gravity? Express your answer in revolutions per minute (rpm).     0.083 rpm     118.3 rpm     0.554 rpm     0.792 rpm

A small child is learning to ride a bike for the first time. Her dad decides it would be a good idea to start her on a small hill. The hill is inclined at 3.40° to the horizontal. The child starts partway down the hill, 4.00 m away from her dad, who stays at the top. She starts to wobble, so her dad sprints toward her from rest with an acceleration of 3.80 m/s2. How far has the child gone before her parent catches her?

3. A satellite is launched from the surface of the earth at the initial speed of 8 km/s. How high will it go before it stops and starts falling back to the earth?

1. Consider an object on some trajectory r(t) and define v = r' as the velocity with speed v = [r'|. (a) Show that we can write v = vT. (b) Show that we can write the acceleration as a = arT + anN where ar and an are the tangential and normal acceleration components that are func- tions of the speed and curvature. Explain why an object with constant speed can still experience an acceleration. (c) Consider a trajectory r(t) = (t² – 1,t – t³). Compute the curvature as well as the tangential and normal components of the acceleration.

The figure below shows an object initially at point A traveling in the +x-direction. It turns in a circular path at constant speed until it is traveling in the +y-direction at point C. The quarter-circle arc from A to C is 245 m in length, and the particle moves from A to C in 38.0 s. Point B on the path is 35.0° below the x-axis. 0 35.0⁰ (a) What is the speed of the object (in m/s)? m/s Need Help? (b) What is the magnitude and direction of the acceleration when the object is at point B? (Enter the magnitude in m/s² and the direction in degrees counterclockwise from the +x-axis.) magnitude m/s² direction Read It counterclockwise from the +x-axis

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QI/ v, m/s 2- Parabolic A particle starts from rest at x = -2 m along x - axis with the v-t history shown. Determine the displacements accelerations at t = 0.5,1.0.1.5 and 2.0 s. and 0.5 1.0 2.0 t,s -1.5 1 Add file

A clown is juggling four balls simultaneously. Students use a video tape to determine that it takes the clown 0.9 s to cycle each ball through his hands (including catching, transferring, and throwing) and to be ready to catch the next ball. What is the minimum vertical speed the clown must throw each ball upward with?

A 15 foot ladder is resting against the wall. The bottom is initially 10 feet away from the wall and is being pushed towards the wall at a rate of 4 ft/sec. How fast is the top of the ladder moving up the wall 12 seconds after we start pushing? 2.