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Acceleration

Inclined Planes and Motion

46) A furniture crate of mass 60.8 kg is at rest on a loading ramp that makes an angle of 25.8 degrees with the horizontal. The coefficient of kinetic friction between the ramp and the crate is .272. What force, (in Newtons) applied parallel to the ramp, is required to push the crate up the incline at a constant speed? 47) A

Laws of Motion: Friction

1. A dockworker is loading 20.2-kg crates onto a ship. He notices that it takes 77.2 Newtons of horizontal force to set them into motion from rest. Once in motion, it takes 58.3 Newtons of horizontal force to keep them moving at a constant speed. Determine the coefficient of static friction. Enter your answer accurate to the thi

Questions about velocity, acceleration & force

(See attached file for full problem description) --- As a vehicle goes from +4m/s to -1 m/s, what is its change in velocity? For 2 and 3 use the following: Vector P: 50 meters @ 110 degrees Vector Q: 35 meters @ 315 degrees Question 2: What is 3P - 3Q? Question 3: What is 2P + 3Q? Question 4: Dick Rutan,

Laws of Motion: Force, Tension and Acceleration

The sled dog in figure drags sleds A and B across the snow. The coefficient of friction between the sleds and the snow is 0.10. a.) If the tension in rope 1 is 150 N, what is the tension in rope 2? Answer: =? N

Atwood Machine Special Cases

I have no clue how to go about getting these equations. Can you help me out and explain how to do these. It is not for a test or anything. It is just a homework problem, but I can't figure it out. (See attached file for full problem description and equations) --- Atwood Machine Special Cases: An Atwood machine consist

Mass hanging from a rope

1. A mass is hung from ropes as shown in the diagram. The rope on the left has a tension T1 = 10.0 N. (A) Draw a free-body diagram of the knot where the three ropes meet. (B) Find the tension T2 in the right-hand rope. (C) Find the mass which is hanging. (Answers: T2 = 27.5 N, m = 2.98 kg.) 2. A 63.0 kg sprinter starts a

Losing Cargo Problem

I am working on a losing cargo problem. I have a box of mass 12.7kg that rests on the flat floor of my truck. My coefficents of friction between the box and floor are u8 =0.180 and uk=0.160. TMy truck stops at a stop sign and then starts to move with an acceleration of 2.15m/s2 . (That s squared.) So if the box is a distan

Tennis problem

At serve a tennis player aims to hit the ball horizontally. What minimum speed is required for the ball to clear the 0.89 m high net about L=14.8 m from the server if the ball is "launched" from a height of H=2.39 m?

Forces and acceleration question

(See attached file for full problem description with diagrams) --- 63. Only two forces act on an object (mass = 4.00 kg), as in the drawing. Find the magnitude and direction (relative to the x axis) of the acceleration of the object... --- (See attached file for full problem description with diagrams)

Atwood machine & rotating rods questions

The first question involves an atwood machine, the second involves two different rods attached to hinges falling/rotating to the ground. See the jpeg for exact questions. The text is provided below simply for the benefit of the search engine: Atwood Machine A frictionless pulley with mass Mb is attached to the ceiling,

Mass of Planets, Gravitational Acceleration and Period of a Pendulum

Find the mass and the radii of the planets Mercury, Neptune and Pluto, masses in kilograms and radii in meters. With that data calculate the gravitational acceleration on each of the planets in kilograms and meters and show the gravitational acceleration in meters per square second. With the gravitational acceleration from abo

Stone Launched Vertically Upward from Top of Cliff

1) Luigi launches a stone vertically upward from the top of a cliff. The height of the stone above the base of the cliff is appoximated by the model h=65+10t-5t^2 where t is time in second and h is height in metres a) how high is the stone above the base of the cliff after 3 seconds? h = 65 + 10t - 5t^2 h = 65 +10(3) -

Physics

1) In the drawing the rope and the pulleys are massless and there is no friction Find a) the tension in the rope, and b) the acceleration of the 12kg block. (The 12 kg block is on the table connected to a 3 kg block which is hanging off the table by a pulley) 2) A chain consisting of five links, each of mass 0.10k

Amplitude of weightlessness

An ant with mass is standing peacefully on top of a horizontal, stretched rope. The rope has mass per unit length and is under tension . Without warning, Throckmorton starts a sinusoidal transverse wave of wavelength propagating along the rope. The motion of the rope is in a vertical plane. What minimum wave amplitude will

Value of gravitational acceleration on moon

A pendulum of length 2 meters is taken to the moon. if this pendulum makes 10 oscillations in 32.0 seconds, what is the value of gravitational acceleration on this moon? a. 3.86 m/s^2 b. 2.54 m/s^2 c. 7.71 m/s^2 d. 9.86 m/s^2

Uniform Circular Motion and Centripetal Acceleration

An ultracentrifuge operates at a speed of 5.00x10^6 rpm. It contains test tubes filled with viruses. (a) what is the centripetal acceleration on a virus at a radial distance of 4.00 cm from the centrifuge's axis of rotation? (b) How does this acceleration compare with g, the acceleration due to gravity?

Uniform Circular Motion and Centripetal Acceleration

The Moon revolves arond the earth in 27.3 days in a nearly circular orbit with a radius of 3.8 x 10^5 km. Assuming that the Moon's orbital motion is a uniform circular motion, what is the Moon acceleration as it "falls" toward the earth?

Linear Momentum and Collisions - Acceleration and Time

A horizontal force of 100 N is applied to a 50.0 kg box; the box slides on a level floor and is opposed by frictional force of 20 N. Show the algebraic steps a) What is the acceleration of the box? b) How long does it take to move 5.0 meters? c) What is its speed at this point (5.0 meters)?

Resultant force and work

The speed of a 4Kg object is given by v=(2t)m/s,where t is in seconds. At what rate is the resultant force on this object doing work at t=1 second?

Kinetic Friction and Tension in a String

A 9 kg hanging weight is connected to a string over a pulley to a 5Kg block that is sliding on a flat table. If the coefficient of kinetic friction is 0.15, find the tension in the string.

Dynamics : Air Resistance and Forces on a Falling Pebble

A person stands on the edge of a cliff and throws a pebble of mass 0.02kg vertically upwards with speed 10m/s. At the instant it is released, the pebble is 50m above sea level. On its return, the thrower does not catch the pebble, which continues past and falls into the sea... (i) Modelling the pebble at a particle and ignoring

Basic Physics: Velocity; Acceleration; Force

Attached are physics questions relating to velocity, acceleration, force etc. Example: A 32.9kg boy and a 59.0kg girl are on the surface of a frozen lake, 13.5m apart. Using a rope, the boy exerts a horizontal 4.15N force on the girl, pulling her toward him. Calculate the magnitude of the boy's acceleration.

KINETIC FRICTION

A BOX IS SLIDING UP AN INCLINE THAT MAKES AN ANGLE OF 16 DEGREES W/ RESPECT TO THE HORIZONTAL. THE COEFFECEINT OF KINETIC FRICTION BETWEEN THE BOX AND THE INCLINE IS 0.18. THE INITIAL SPEED OF THE BOX AT THE BOTTOM OF THE INCLINE IS 3.0 M/S. HOW FAR DOES THE BOX TRAVEL UP THE INCLINE BEFORE COMING TO REST?

KINETIC FRICTION

A 3.8KG BOX IS SLIDING ACROSS THE HORIZONTAL FLOOR OF AN ELEVATOR. THE COEFFICIENT OF KINETIC FRICTION BETWEEN THE BOX AND THE FLOOR IS 0.470. DETERMINE THE KINETIC FRICTIONAL FORCE THAT ACTS ON THE BOX FOR EACH CASE. THE ELEVATOR IS STATIONARY THE ELEVATOR ACCELERATES UPWARDS AT 2.0 M/S2 THE ELEVATOR ACCELERATES DOWNWARD A