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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

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

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

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

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

Jet catapulted from aircraft carrier

On an aircraft carrier, a jet can be catapulted from 0 to 180 mi/h in 2.00 s. If the average force exerted by the catapult is 4.40 x E6 N what is the mass of the jet? I converted 180 mi/h to 80.45 m/s I found the acceleration to be 40.23 m/s^2 To find mass I used m=F/a and got 109.3kg

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) -

Calculate the velocity acceleration and position of the cart.

An air track cart attached to a spring completes one oscillation every 2.5 s. At t=0 the cart is released from rest at a distance of 15 cm from its equilibrium position. Calculate the velocity and acceleration of the cart at t=0.25 s. and t=0.75 s. Determine the position of the cart at t=0.2 s and t=0.45 s.