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Upward Acceleration

Mass m1 (34.50 kg) is on a horizontal surface, connected to mass m2 (5.90 kg) by a light string. The pulley has negligible mass and no friction. A force of 220.9 N acts on m1 at an angle of 34.50 degrees. The coefficient of kinetic friction between m1 and surface is .233. Determine the upward acceleration of m2. I have at

Acceleration in a Simple Pulley System

A 14 kg monkey climbs up a massless rope that runs over a frictionless tree limb and back down to a 27 kg package on the ground. What is the magnitude of the last acceleration the monekey must have if it is to lift the package off the the ground?

Force and Newton's Laws

A 3.5 kg block is put on top of a 6 kg block. To cause the top block to slip on the bottom one, while the bottom one is held fixed, a horizontal force of at least 15.4 N must be applied to the top block. The assembly of blocks is now placed on a horizontal frictionless table. Please explain how to: 1. Find the magnitude

Projectile motion of a skier

A skier is accelerating down a 30 degree hill at 3.80 m/s^2. Draw a convenient XY coordinate system, then determine: a) What is the vertical component of her acceleration? b) How long does it take her to reach the bottom, assuming she starts from rest and accelerates at a constant rate, if her elevation change is 355m?

Constant Acceleration Question

A bullet traveling horizontally at a speed of 350 m/s hits a board perpendicular to the surface, passes through and emerges on the other side at a speed of 210 m/s. The board is 0.04 m thick, how long does the bullet take to pass through it?

Calculating area of an ice sheet

A 300 kg polar bear walks onto a .42 m thick chunk of ice, while it is floating in the arctic ocean. What is the area of the sheet if it sinks just level with the surface while supporting the bear?

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

Vectors and Vertical Component of Acceleration

Please see attached for the figure. (a) A skier is accelerating down a 30.0 degree hill at 4.30 m/s^2. What is the vertical component of her acceleration? (m/s^2 (downward)) (b) How long will it take her to reach the bottom of the hill, assuming she starts from rest and accelerates uniformly, if the elevation change is 330

Kinematics: Car Strikes a Tree

A car traveling at 95 km/h strikes a tree. The front end of the car compresses and the driver comes to rest after traveling 0.77 m. What was the average acceleration of the driver during the collision? Express the answer in terms of "g's," where 1.00g = 9.80 m/s2.

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

A Swinging Pendulum

What do I need to know to be able to sketch the graphs for a ball tossed upward toward a motion detector (mounted from your lab table) as it moves up, reaches its highest point, and falls back down?

A Cart on a Track

A cart on a track is attached to a mass via a string hung over a pulley. If the hanging mass is kept constant, does the acceleration of the cart increase, decrease, or remain the same as the mass of the cart is increased? Explain.

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?

Equations of Constant Angular Acceleration

Placed on a long incline, a wheel is released from rest and rolls for 30.0 s until it reaches a speed of 10.0 rad/s. Assume its acceleration is constant, what angle did it turn through?

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.