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Acceleration

Will the rope break?

A 40kg bucket is being lifted by a rope. The rope is guaranteed not to break if the tension is 500N or less. The bucket, started from rest, after being lifted for 3m, it is moving at 3m/s. Assuming that the acceleration is constant, is the rope in danger of breaking? Justify your answer by including the tension in the rope.

One-Dimensional Motion with Constant Acceleration

Two cars are traveling along a straight line in the same direction, the lead car at 25.3 m/s and the other car at 29.3 m/s. At the moment the cars are 38.9 m apart, the lead driver applies the brakes, causing her car to have an acceleration of -1.93m/s^2. Therefore, it travels 166 meters in this time and takes 13.1 to stop. Q

Acceleration of Rocket Sled

1) A rocket sled running on a straight level track has been used to study the physiological effects of large accelerations on astronauts. One such sled can attain a speed of 408m/sec in 1.6sec. starting from rest. a) What is the acceleration of the sled, assuming it is constant? Answer in m/s^2. b) How many g's would

Vibrations problems

1) If the complex number 5+2i is expressed in the exponential form Ae^io, determine the values of A and O. a)3.3754, 32.70 b)4.6483, 27.50 c)5.3852, 21.80 d)6.6722, 15.55 2) A harmonic motion has an amplitude of 0.05m and a frequency of 10Hz. Determine the maximum velocity. a)1.571m/s b)3.142m/s c)4.672m/s d)

General conceptual physics help

1. What is the acceleration of a 20kg sled as it is pulled across the ground with an applied force of 50N? The force of friction working against the sleds motion is 30N. 2. A railroad deisel engine coasting at 10km/h runs into a stationary flatcar. The deisel weighs 4 times as much as the flatcar. Assuming the cars couple tog

Dynamics Problem: Acceleration

A car starts from rest and moves along a straight line with an acceleration of a = (3s^(-1/3)) m/s^2, where s is in meters. Determine the car's acceleration when t = 4s.

Acceleration of a rock and a sky diver

1. What is the acceleration of a rock at the top of its trajectory when thrown straight upward? Explain whether or not the answer is zero by using the equation a=F/m as a guide. 2. What is the acceleration of a sky diver when air resistance is half the weight of the sky diver?

Angle of turn

A pulley has an initial angular speed of 12.5 rad/s and a constant angular acceleration of 3.41 rad/s squared. Through what angle does the pulley turn in 5.26 s?

Circular Motion and Weight

A 587 kg roller coaster car (includes mass of occupants) are passing through a vertical loop. The speed of the car at the top of the loop is 15.4 m/s. What radius of curvature (in meters) must the loop have at its very top in order for the occupants to experience a normal force which is 1/3 their weight? Two students sitting

Rotational dynamics: Rolling of ring and disc from incline

A solid disk and ring of the same mass and radius start from rest at the top of an incline. both of them start from the same vertical height of 0.5m and roll down an incline. Which of these reach the bottom first? Give reason. Find the speed of the disk when it reaches the bottom of the incline.

Harmonic Motion and Gravitational Pull

You need to know the height of a tower, but darkness obscures the ceiling. You note that a pendulum extending from the ceiling almost touches the floor and that its period is 12s. The acceleration of gravity is 9.81 m/s2. How tall is the tower in units of m?

Multiple physics problems

A bullet of a mass of 20 grams leaves the barrel of a rifle with a velocity of 700m/s. The length of the barrel is 60 cm. a. What is the average acceleration of the bullet as it travels the length of the barrel. b. Find the average force on the bullet as it travels inside the barrel. c. Suppose the rifle is 1m above the surfa

Rope tension and a frictionless incline

A 80kg crate is pulled up a frictionless incline of 30 degrees by a rope with an acceleration of 1.5 ms^2. If the rope is parallel to the incline, what is the tension in the rope, assume g = 9.8 ms^2?

Mechanics: force and Acceleration

On my last test, there is a question: an object with a mass of 5kg is acted upon by 4 separate forces that each have a magnitude of 10N. I understand that there could be different resulting accelerations of the object but i don't understand why or how which is why i got this answer wrong. In fact, i was totally lost. What are th

Calculating Angles to Solve Problems

3) A batter swings and hits a fly ball in baseball, giving it an initial velocity of 35 m/s at an angle of 40 degrees from the horizontal. The ball is impacted at 1 meter above the ground. The baseball undergoes a parabolic path that is set to just clear a 3 meter fence in center field. The center fielder, 27 meters away from th

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

Earthquake causing objects to leave the ground

An earthquake-produced surface wave can be approximated by a sinusoidal transverse wave. Assuming a frequency of 0.476 Hz (typical of earthquakes, which actually include a mixture of frequencies), what minimum amplitude will cause objects to leave contact with the ground?

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

Rate of acceleration and tension of wire in pulley problem

Please explain how to find acceleration of the system and tension of the wire in the following case: A mass (m=1.4kg) sits on a frictionless table. Another mass is connected to it by a wire over a frictionless pulley (mass of second object = 1.6kg). See attached file for figure.

AP Physics Questions

Question 69: A student proposes a design for an automobile crash barrier in which a 1700-kg sport utility vehicle moving at 20.0 m/s crashes into a spring of negligible mass that slows it to stop. To avoid injuring the passengers, the acceleration of the vehicle as it slows can be no more than 5.00g. a) Find the required

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,

Rotational Dynamics: Atwood's Machine

A m1 = 16.0 kg object and a m2 = 12.5 kg object are suspended, joined by a cord that passes over a pulley with a radius of 10.0 cm and a mass of 3.00 kg (Fig. P10.46). The cord has a negligible mass and does not slip on the pulley. The pulley rotates on its axis without friction. The objects start from rest 3.00 m apart. Treatin

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

Significance of normal force - an example

A 5.0 kg block is pulled along a horzontal surface by a cord that exerts a force T = 12.0 N at an angle 35 degrees above the horizontal. There is no friction (A) Draw a free-body diagram of the block, labeling all forces. (B) What must be true of the sum of the vertical components of all forces? Why? (C) Determine the accelerati