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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

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

Calculating height at pinnacle

The setter on the volleyball team recieves a bump and sets a ball starting from net height (2.30 m above the gym floor) straight up with a velocity of 7.27 m/s. How high off the gym floor will the ball be when it reaches the pinnacle? If the ball fell from the pinnacle straight down how fast would it be moving when it hit th


It's first and ten. let's call the line of scrimmage the origin. The coach calls a dive (a staright ahead running play.) The line does a great job and opens a huge hole for the running back. If the running back gets the hand-off 4.0 yards behind the line of scrimmage with an initial speed of 3.0 yards/sec and accelerates at

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

Maximum acceleration

The maximum load that can safely be supported by a rope in an overhead hoist is 400N. What is the maximum acceleration that can safely be given to a 25 kg object being hoisted vertically upward?

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.

Force, Mass and Acceleration

F = MA F = Force (measured in Newton's) M = Mass (measured in Kilograms) A = Acceleration (measured in Meters per second per second) (m/s^2) What is the answer? 1. F= _________ where; M = 100Kg and A = 5 m/s^2 F = MxA F = ___________X ________ = ______________ 2. F= _________ where; M = 10Kg and A = 50 m/s

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

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.

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.)

Forces, free body diagrams, and work

Please give complete solutions step by step. Thanks again for helping me! 1. A box is touching the floor. The normal force of the floor on the box depends on... (see attachment for rest)

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

Free Body Diagrams

Use the Free-body diagrams to answer the following: 1. You are driving along the highway, when the car in front of you makes a right-hand turn. What is the best free-body diagram of forces on the turning car, from your point of view behind the car? 2. The speed of the car in front of you is a constant 25m/s. The mass of th

Acceleration, tension

4.) A 0.840 kg glider on a level air track is joined by strings to two hanging masses. The strings have negligible mass and pass over light, frictionless pulleys. a.) Find the acceleration of the masses and... b.) Find the tension in the strings when the air flow is turned off and the coefficient of friction between the glide

Acceleration and collision

1) You are playing an air hockey game where a puck glides frictionless on a cushion of air on a flat level table. When the puck is gliding across the table at constant velocity, which statement is true? There are no forces acting on the puck There is a force on the puck that causes it to continue to move forward. The vecto

Kinematics graph

Please give step by step answers. The four question that follow belong to the graph being described. The graph has velocit on the y axis in m/s and the x axis is time in seconds. The points given make the grph line. Points (0,20), (2,30), (4,40), (6,40), (8,0), and (10,-30). 1) What is the velocity of the object at t=2

Calculating density, acceleration, mass, and distance

Please give an answer and explanation with steps if needed. 1) A block of material has dimensions 3.8cm by 6.1 cm by 3.8cm. Its mass is 594g. What is the density? Answer in units of g/cm^3 2) An acceleration of 4.2 mi/h/s is equal to: Answer in units of m/s^2. 3) Grains of fine beach sand are assumed to be spheres

Simple Acceleration

Car A is at rest (0 mi/hr), while car B is going 90m/hr with constant velocity. How fast will car A have to travel from rest in order to catch up to car B over a distance of 3 miles? How long will it take for car A to catch car B?

Angular Momentum and Centripetal Force

A car of mass 1000kg moves with a speed of 50 m/s on a circular track of radius 100m. What is the magnitude of its angular momentum (in kg.m^2/s) relative to the center of the racetrack? ============================================== Answers: a) 5 x 10^2 b) 5 x 10^6 c) 2.5 x 10^6 d) 2.5 x 10^4 ############################

Calculations Using Newton's 2nd Law

1. A ball that weights 5N falls on earth ...what is the net force that acts on the ball during the fall? Which is the force (including its direction) that the ball exercises on the land when it falls? 2. In the moon, the gravitational acceleration of the objects is around 1.67 meter/s2 How much does it weight in the moon an ob

Force, Newton's 2nd law

1. If a cord is pulled upward, making an angle of 27º with respect to the horizon line, produces a force of 365N and can pull a box over the floor with a weight of 55.2 kg at a constant speed of 20.5 centimeters/sec - which is the magnitude of the friction force that opposes the movement of the box? 2. A boat pulls a water-ski

For OTA 103997 or 103877 only/Calculus Help

1. The position equation for the movement of a particle is given by when s is measured in feet and t is measured in seconds. Find the acceleration at two seconds. 2. Find the derivative: . 3. Find if . 4. The radius of a circle is increasing at the rate of 5 inches per minute. At what rate is the area increasing when