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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.

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

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.

Mechanics: 14 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

Newton's Law of Motion

A 20-kg child sits on a 5-kg sled and slides down a 125-meter, 31-degree slope, to the nearest m/s what is his or her speed at the bottom?

Newton's Law of Motion

A child pulls a wagon with a force of 37 N by a handle making an angle of 30 degrees with the horizontal. If the wagon has a mass of 4.5 kg, to the nearest hundredth of a m/s2 what is the acceleration of the wagon? To the nearest newton what would be the minimum force applied at that angle which would lift the wagon off the g

Newton's Law of Motion

The red box has a mass of 20 kg and the blue box has a mass of 11.1 kg and the Force is 220 N. To the nearest tenth of a m/s2, what is the acceleration of the combination? To the nearest newton what force does the blue box exert on the red box?

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?

Find an equation of motion and differentiate to find acceleration.

Please find details of problem on attached PDF file. I desperately need an answer to this problem straight away so if you cannot start working on an answer immediately please do not sign-out my problem. Thank you PS Please can you go through the steps required to transpose the equation clearly.

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)