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Kinematics and Forces Problem Set

1) Please answer T or F and tell why true or false. a) A body can be accelerating even when it is not moving. b) The velocity of an accelerated body changes with time. c) Motion and acceleration are not the same quantity d) The words motion and acceleration can be used interchangeably. e) The acceleration of a body with zer

Simple harmonic motion and maximum amplitude of oscillation

A large block P executes horizontal simple harmonic motion as it slides across a frictionless surface with a frequency f. Block B rests on top of block P and the static coefficient of static friction between the two is mu_s. What maximum amplitude of oscillation can the system have if the upper block is not to slip? I am no

Angular Acceleration Alpha of Uniform Board

A uniform board of mass m and length L is pivoted on one end and is supported in the horizontal position by a rope attached to the other end. Another rope, attached to the board a distance L/3 from the pivot point, is being pulled straight down with a constant force of magnitude F. Suddenly, the rope attached to the end of the b

The Round Trip

A cyclist competes in a one-lap race arond a flat, circular course of radius r. Starting from rest and speeding up at a constant rate throughout the race, the cyclist covers the entire course in a time delta t. The mass of the bicycle (including the rider) is m. Which of the following quantities are constant in this problem? (No

Spring Mass System - Constant Acceleration or Velocity

A mass m is hanging from a spring, stiffness k, in an elevator. The elevator is at rest and the system is in equilibrium. Then the elevator starts to move. Calculate the amplitude and the phase of the oscillations of the spring for 2 situations: a) the elevator moves suddenly and then has a constant velocity v. b) the elevator

Sign of Acceleration Table

Please do not place your response in a .pdf or .cdx format, but Word documents are okay. Thanks! Here's the actual problem: A) If an object is speeding up and moving away from the motion detector, is the acceleration positive or negative? B) If an object is speeding up and moving toward the motion detector, is the accel

Angular Acceleration of a Ladder

At a given instant the top B of the ladder has an acceleration Ab= 2ft/s^2 and a velocity of Vb=4ft/s, both acting downward. Determine the acceleration of the bottom A of the ladder, and the ladder's angular acceleration at this instant (see attachment for diagram).

The constant angular acceleration of wheels

A wheel is revolving at 20.0 rad/s when a brake is engaged and the wheel is brought to a uniform stop in 15.92 revolutions. How long did it take to stop the wheel and what was the deceleration?

Magnitude of Horizontal and Vertical Acceleration

A block of mass m1 is attached to a massless, ideal string. This string wraps around a massless pulley and then wraps around a second pulley that is attached to a block of mass m2 that is free to slide on a frictionless table. The string is firmly anchored to a wall and the whole system is frictionless. Use the coordinate sys

The Rope Pull

On a bright sunny day, two girls play tug of war while standing on the opposite sides of a pond. Initially, each stands at a distance from her edge of the pond. Jackie, who weighs less than her opponent Sue, loses the tug of war and is forced to take a dive in the pond. (Most often, the tug of war is won by the heaviest, not the

Don't Rock the Block

PSS 5.1: Don't Rock the Block Learning Goal: To practice Problem-Solving Strategy 5.1 for equilibrium problems. A pair of students are lifting a heavy trunk on move-in day . Using two ropes tied to a small ring at the center of the top of the trunk, they pull the trunk straight up at a constant velocity . Each rope makes an a

Motion of a Block with Three Forces

Motion of a Block with Three Forces Three forces of magnitudes , , and are applied to a mass , initially at rest, at angles shown on the diagram. In this problem, you will determine the resultant (total) force vector from the combination of the three individual force vectors. All angles should be measured counterclockwise

Acceleration and Tension

A solid roll of paper falls off the countertop, the outward sheet still held on the counter by a large can of beans. The diameter of the roll is 14cm, and its mass is .2kg (consider constant). Find: a) The acceleration of the roll's center of mass. b) The tension in the outward sheet of paper.

Mass of the Pulleys and the Cord Problem

At a given instant the 10-lb block A is moving downward with a speed of 6 ft/s. Determine its speed 2 seconds later. Block B has a weight of 4 lb, and the coefficient of kinetic friction between it and the horizontal plane is uk=0.2. Neglect the mass of the pulleys and the cord. See attachment for diagram.

Angular momentum, pebble,wheel

You are to find the coordinates of a pebble stuck in the tread of a rolling tire that is rotating counterclockwise (i.e., in the positive sense) with angular velocity w. The tire rolls without slipping on the ground (which is at y=0 ). The outer radius of the tire is R. At time t=0 , the pebble is at the top of the tire, as show

Conservation of Angular Momentum and Apparent Free-Fall Acceleration

A space station is shaped like a giant wheel and has a radius of 100 metres and a moment of inertia of 5.00 x 10^8 kg m^2. A crew of 150 is living on the rim. Assume average mass for a crew member as 65 kg. The station's rotation causes the crew to experience an apparent free-fall acceleration of g. 100 of the crew members m

Car Along Curved Path

A car travels along the curved path with radius of curvature p= 30m such that its speed is increased by v= (0.5e^t) m/s^2 , where t is in seconds. Determine the magnitudes of its velocity and acceleration after the car has traveled s= 18m starting from rest. Neglect the size of the car.

Calculating acceleration and mass

The 100 kg block in the figure takes 5.50 s to reach the floor after being released from rest. What is the mass of the block on the left? Please see attachment for diagram.

Ball Speed and Acceleration

Please do not include your response in a .pdf format if at all possible, but Word documents are okay. Thanks! Here's the question: A 2.0 kg ball swings in a vertical circle on the end of an 80-cm-long string. The tension in the string is 20 N when its angle from the highest point on the circle is theta = 30 degrees. (a)

Car on Inclined Plane Mechanics Problem

A car is on an inclined plane (shoulder of the road) at angle theta. The car has mass of 1.6Mg and center of mass at G. G is located 2.5 ft vertical from the inclined plane (shoulder of the road). If the coefficient of static friction between shoulder of road and tires is us=0.4, determine greatest slope, theta, the incli

Circular Launch (Centripetal Acceleration)

A ball is launched up a semicircular chute in such a way that at the top of the chute, just before it goes into free fall, the ball has a centripetal acceleration of magnitude 2g. How far from the bottom of the chute does the ball land? (Your answer for the distance the ball travels from the end of the chute should contain R

Motion in two dimensions

You are asked to consult for the city's research hospital, where a group of doctors is investigating the bombardment of cancer tumors with high-energy ions. The ions are fired directly toward the center of the tumor at speeds of 6.00E6 m/s. To cover the entire tumor area, the ions are deflected sideways by passing them between t

Projectile Motion Problem

A projectile is fired from ground level at time t=0, at an angle [THETA] with respect to the horizontal. It has an initial speed V0. In this problem we are assuming that the ground is level ... **Please see attachment for proper citation of symbols and complete question.

Movement on an Inclined Plane

A block is given an initial speed of 4.0 m/s up a 22° plane. (a) How far up the plane will it go? (b) How much time elapses before it returns to its starting point? Ignore friction.

Rocket Acceleration Problem

A Saturn V rocket has a mass of 2.75 x 10^6 kg and exerts a force of 33 x 10^6 N on the gases it expels. Determine (a) the initial vertical acceleration of the rocket, (b) its velocity after 8 seconds, and (c) how long it takes to reach an altitude of 9500m. (Ignore the mass of gas expelled and assume g remains constant.)

Coefficient of friction and dynamic and static friction

It's not a problem but I need a good explanation please because I really don't understand: I need someone to explain why when we have (for example) one block on another, why when we represent the friction force, its direction can sometimes become, in the same sense, not only direction but also acceleration? How is this possib

Physics: Horizontal force applied to a radio at rest; friction, acceleration

1.) A horizontal force of 3.00 N is applied to a 1.00-kg radio, initially at rest on a table with a level surface. a.) Will the radio move if the coefficient of the friction is 0.45? b.) What is the coefficient of friction if it just begins to move? c.) What is its acceleration if the coefficient of the friction is only 0.0