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Classical Mechanics: Momentum and Velocity

A 4.0 kg toy race car can move along an x axis. The figure below gives Fx of the force acting on the car, which begins at rest at time t = 0. (The vertical axis is marked in increments of 2 N.) See the attached document for the necessary graph. (a) What is the momentum of the car at t = 6.0 s (b) What is the moment

Work and Average Acceleration

Zak, helping his mother rearrange the furniture in their living room, moves a 50-kg sofa 6 meters with a constant force of 20 newtons. Neglecting friction, a. What is the work done by Zak on the sofa? b. What is the average acceleration of the sofa?

Determining Acceleration of a Block: Example Problem

A 42.0 Kg block of ice slides down a plane with an incline of 34 degrees. Assuming friction is negligible, what is the acceleration of the block down the incline? 1. 9.80 m/s^2 2. 6.61 m/s^2 3. 8.12 m/s^2 4. 5.48 m/s?

Friction: Acceleration of Two Blocks on an Incline

Two blocks, of weights 3.6 N and 7.2 N, are connected by a mass-less string and slide down a 30 degree inclined plane. The coefficient of kinetic friction between the 3.6 N block and the plane is 0.10, while there is no friction between the 7.2 N block and the plane. Determine: a) the acceleration of each of the blocks b) th

Physics - Classical Mechanics - Rotational Motion

An astronaut is being tested in a centrifuge. The centrifuge has a radius of 10 m and, in starting, rotates according to theta = (0.30 rad/s?t? where t is in seconds and theta is in radians. When t = 5.0 s, what are the magnitudes of the astronaut's (a) rotational velocity, (b) translational velocity, (c) tangential accele

Moving velocity and mechanics

An airplane was moving with a velocity equal to 300 mph when the velocity was increased with uniform acceleration to 600 mph in 15 min, calculate the number of miles the airplane traveled during that interval of time

Simple Harmonic Motion: Frequency for vertical Oscillations

A hanging wire has a length of 1.90m. When a steel ball of mass 50.0kg is suspended from the wire, the wire stretches by 2.30mm . If the ball is pulled down a small additional distance and released, at what frequency will it vibrate? Assume that the stress on the wire is less than the proportional limit. Take the free fal

Gravitational Force and Acceleration

Concept Question: A large rock and a small pebble are held at the same height above the ground. (a) Is the gravitational force exerted on the rock greater than, less than or equal to that exerted on the pebble? Justify your answer. (b) When the rock and the pebble are released, is the downward acceleration of the rock gre

Friction: Box in a Truck

Consider a box in back of a pickup truck. 1. If the truck accelerates slowly, the box moves with the truck without slipping. What force or forces act on the box to accelerate it? In what direction do these forces point? 2. Draw a free body diagram of the box 3. What happens to the box if the truck accelerates too rapi

Discuss the Problem-Solving Process outlined. Which step is the most important? Could students solve problems without one of these steps? Give an example of a problem and demonstrate its solution through the four steps. Four-Step Problem-Solving Process 1. Understanding the problem a. Can you state the problem in your own words? b. What are you trying to find or do? c. What are the unknowns? d. What information do you obtain from the problem? e. What information, if any, is missing or not needed? 2. Devising a plan The following list of strategies, although not exhaustive, is very useful: a. Look for a pattern. b. Examine related problems and determine if the same technique applied to them can be applied to the current problem. c. Examine a simpler or special case of the problem to gain insight into the solution of the original problem. d. Make a table or list. e. Make a diagram. f. Write an equation. g. Use guess and check. h. Work backward. i. Identify a subgoal. j. Use indirect reasoning. k. Use direct reasoning. 3. Carrying out the plan a. Implement the strategy or strategies in step 2 and perform any necessary actions or computations. b. Check each step of the plan as you proceed.This may be intuitive checking or a formal proof of each step. c. Keep an accurate record of your work. 4. Looking back a. Check the results in the original problem. (In some cases, this will require a proof.) b. Interpret the solution in terms of the original problem. Does your answer make sense? Is it reasonable? Does it answer the question that was asked? c. Determine whether there is another method of finding the solution. d. If possible, determine other related or more general problems for which the techniques will work.

Discuss the Problem-Solving Process outlined. Which step is the most important? Could students solve problems without one of these steps? Give an example of a problem and demonstrate its solution through the four steps. Four-Step Problem-Solving Process 1. Understanding the problem a. Can you state the problem in your ow

Projectile Motion: Minimum Speed of to Cross a Log

Please help - hope you can explain me the steps also: A cylindrical tree trunk with a circular cross-section has a diameter of 20 cm. The trunk rests horizontally on the flat ground. A grasshopper jumps from the ground on one side of the tree trunk to the ground on the other side without touching the tree trunk. What is the m

Bungee jumping: Kinematics, energy and period of oscillations

Your adventurous friend Lola goes bungee jumping. She leaps from a bridge that is 100 m above a river. Her bungee cord has an unstretched length of 55 m and a spring constant k=750 N/m. Lola has a mass of 45kg 1. How fast is she falling when she just starts to stretch the cord? How long does it take for Lola to reach this poi

Circular motion of conical pendulum

Consider a conical pendulum with a 80.0 kg bob on a 10.0 m wire making an angle of θ = 5.00° with the vertical. (Consider + to be towards the center of the circular path.) (a) Determine the horizontal and vertical components of the force exerted by the wire on the pendulum. _____N +_____N (b) What is the radial

Four problems on dynamics.

Please see attachment for fig. 24. Pictures below (see attachment) show the loads hanging from the ceiling of an elevator that is moving at constant velocity. Find the tension in each of three strands of cord supporting each load. 26. Angle phi =15 degree. Assuming the block start from the rest at the top and that the leg

Newton's Law of Motion: Contact Force and Acceleration

Two crates, of mass 75 kg and 107 kg, are in contact and at rest on a horizontal surface. A 732 N force is exerted on the 75 kg crate. If the coefficient of kinetic friction is 0.15, calculate the following: (a) the acceleration of the system in m/s/s. (b) the force that each crate exerts on the other in N.

Acceleration of the elevator and tension of the rope

How much tension must a rope withstand if it it used to accelerate a 1700 kg car vertically upward at 0.4 m/(s ^2)? A person stands on a bathroom scale in a motionless elevator. When the elevator begins to move, the scale briefly reads only 0.65 of the person's regular weight. What are the direction and magnitude of the acc

block sliding down a frictionless incline

Please see the attached file. A block of mass m = 2.00 kg is released from rest at h = 0.400 m from the surface of a table, at the top of a theta = 40.0 degrees incline as shown below. The frictionless incline is fixed on a table of height H = 2.00 m. (a) Determine the acceleration of the block as it slides down the incli

Rotational Dynamics: Acceleration of Mass

1. What is the acceleration of a system consisting of two masses, of 200 grans and 215 grams, respectively, tied at the end of a light cord passing over a frictionless pulley of 150 grams mass and 4 cm. radius, if the masses start at the same level from rest? 2. A string is wound on the edge of a disk weighing 2.5 kg and havi

Average Acceleration of Nitrogen Molecule in Air

The average speed of a nitrogen molecule in air is about (6.70 x 10^2) m/s, and its mass is about (4.68 x 10^-26) kg. (a) If it takes (3.00 x 10^-13) seconds for a nitrogen molecule to hit a wall and rebound with the same speed but moving in an opposite direction (assumed to be the negative direction), what is the average acc

Newton's Laws of Motion: Acceleration, Pulley and Incline

The following equations describe the motion of a system of two objects: +n - (5.00 kg)(9.8 m/s2)cos 15.0° = 0 fk = 0.360n +T + (5.00 kg)(9.8 m/s2)sin 15.0° - fk = (5.00 kg)a -T + (3.10 kg)(9.8 m/s2) = (3.10 kg)a (a) Solve the equations for a and T. a (in m/s2)= T (in N)= In what situation might these equations be u

Simple harmonic motion

Please see the attached file. A piston executes simple harmonic motion with amplitude of 0.1 m. If it passes through the center of its motion with a speed of 0.5 m/s, what are the maximum accelerations and the period of oscillation?

System of three particles

Consider a system of three particles, each of mass m, whose motions are described by {m_1a_1 = F_12 + F_13, m_2a_2 = F_21 + F_23, m_3a_3 = F_31 + F_32}. If particles 2 and 3, even though not rigidly bound together, are regarded as forming a composite body of mass 2m located at their mid-point r = (1/2)*(r_2 + r_3), find the

A set of 19 problems on dynamics.

I need help with the following problems and all the circled ones in the attached file, numbers 22, 23, 14, 7, 8. 22. A moving object is acted on by a net force. Give an example of a situation in which the object moves (a) in the same direction as the net force; (b) at right angles to the net force; (c) in the opposite di

Motion in 2D: Maximum range of projectile down the incline

1) a) Find the angle required to maximize the range down an incline which is pitched at an angle of −θ with respect to the horizontal and the projectile is shot an angle of φ above the incline at a speed of v0 . b) Determine the distance down the incline at the angle found in a). c) Plot the trajectory gi

Motion of particle suspended by string, in horizontal plane

(Please see the attached file) A particle is attached to one end of a light inextensible string. The other end of the string is attached to a fixed point O. The particle is set into motion, so that it describes a horizontal circle whose centre is vertically below O. The angle between the string and the vertical is theta, as s

Minimum Wave Amplitude

A large ant is standing on the middle of a circus tightrope that is stretched with tension T_s. The rope has mass per unit length mu. Wanting to shake the ant off the rope, a tightrope walker moves her foot up and down near the end of the tightrope, generating a sinusoidal transverse wave of wavelength lambda and amplitude A. As

Force and acceleration

Please see attachment. 11. What is the weight of a 2.50-kg bag of sand on the surface of the earth? 12. A 2.00-kg projectile is fired at an angle of 20.0 degrees. What is the magnitude of the force exerted on the projectile when it is at the highest position of its trajectory? 13. A 44-kg child steps onto a scale and the s

circular motion explanation

Please see attachment. Thank You your help is greatly needed. 1. A ball moves with a constant speed of 4 m/s around a circle of radius 0.25 m. What is the period of the motion? 2. A racecar is traveling at constant speed around a circular track. What happens to the centripetal acceleration of the car if the speed is doubled

the acceleration of the ladder extension on the firetruck

The firetruck us moving forward at a speed of 35 MPH and is decelerating at a rate of 10ft/sec.^2. Simultaneously, the ladder is being raised and extended. At the instant considered the angle Ø is 30° and is increasing at a rate of 10 degrees/sec . Also at this instant the extension b of the ladder is 5 ft and Vb = 2 feet /