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Acceleration of Object Rolling Down an Incline

1. Assume you are walking in front of a motion sensor that graphs the distance you have walked (y axis) against time (x axis). Describe the motion that you need to make to produce the following graphs: a) Line with a positive slope. b) Line with steeper positive slope. c) Line with negative slope. d) Line with zero slope.

Velocity, Acceleration and Force

1. A body with initial velocity 8.0 m/s moves along a straight line with constant acceleration and travels 640 m in 40 s. For the 40 s interval, find (a) the average velocity, (b) the final velocity, and (c) the acceleration. 2. A mass of 10 kg is hanging from a spring scale that is in turn hanging from a hook attached to the

Acceleration and Velocity of a Particle

1. A particle oscillates between the points x = 40 mm and x = 160 mm with an acceleration a = k( 100 - x), where a and x are expressed in mm/ s^2 and mm, respectively, and k is a constant. The velocity of the particle is 18 mm/ s when x = 100 mm and is zero at both x = 40 mm and x = 160 mm. Determine (a) the value of k,( b) the

Electromagnet, magnetic force, positive ion, parallel wire, coil

A laboratory electromagnet produces a magnetic field of magnitude 1.50 T. A proton moves through this field with a speed of 6.00 x 10^6 m/s. (a) Find the magnitude of the maximum magnetic force that could be exerted on the proton. (b) What is the magnitude of the maximum acceleration of the proton? (c) Would the field exert the


1. In chronological order, what happens to the kinetic, potential, and total energy of the cart for one half cycle. The half cycle starts just after you have pushed the cart. The half cycle finishes just when the cart stops at the height of its motion. Remember, this is about the cart's mechanical energy. A. Kinetic goes fro

Circular Motion

1. Centrifuges are commonly used in biological laboratories for the isolation and maintenance of cell preparations. For cell separation, assume centrifugation conditions that are 1.00 x 103 rpm using an 8.31-cm-radius rotor. What is the radial acceleration of material in the centrifuge under these conditions? Express your answer

Instantaneous and Average speeds and Average acceleration.

A runner is jogging at a steady velocity of 3.3 km/hr. When the runner is at 8.6Km from the finishing line, a bird begins flying from the runner to the finishing line at 13.2 km/hr. When the bird reaches the finish line, it returns around and flies back to the runner. How far does the bird travel? Answer in units of Km..... and

Cash receipts acceleration system

Peggy Pierce Designs Inc. is a vertically integrated, national manufacturer and retailer of women's clothing. Currently, the firm has no coordinated cas management system. A proposal, however, from the first Pennsylvania Bank aimed at speeding up cash collections is being examined by several of Pierce's corproate executives.

Two pulley system supporting two masses; one sliding on a rough surface and the other hanging. The system is released from rest. To determine the linear acceleration of the sliding mass. Block A weighs 25 lbs and it slides on a surface with a coefficient of friction 0.30. Block B weighs 7 lbs. The cable does not slip on eithe

Mechanics: Seven multiple choice questions

1. What is the tangential speed of Nairobi, Kenya, a city near the equator? The earth makes one revolution every 23.93 h and has an equatorial radius of 6380 km. A) 74.0 m/s B) 116 m/s C) 148 m/s D) 232 m/s E) 465 m/s 2. The radius of the earth is 6.38 x 106 m and its mass is 5.98 x 1024 kg. What is the accelerat

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

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

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

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

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 /

Force: Motion on an incline with friction.

Problem: The incline is 30 degrees with a kinetic friction coefficient of 0.20. Initially the system is not moving. It is given a push uphill at 1m/s and there is a total distance of 1.5m from initial point to the end of the incline. a. Minimum coefficient of friction to keep the system from moving initially b. Whe

Relative Motion and Energy

See Attachments Please include all FBD and explanations. 1. The launch catapult of an aircraft carrier gives the 7Mg jet airplane gives the airplane a constant acceleration and launches the airplane in a distance of 100 m measured along the angled takeoff ramp. The carrier is moving at a constant speed of 16 m/s. If an ab

Rocket driven car - Expression for acceleration

Please see attachment for full problem description. A rocket-driven car of total mass M loses mass at a constant rate lembda per unit of time at a constant ejection speed V relative to the car. If the total resistance to motion is kv with the speed is v, show that the acceleration of the car along a straight horizontal road i

Parametric Equations : Describing the Motion of a Ball

A baseball pitcher throws a baseball with an initial velocity of 133 feet per second at an angle of 20° to the hoizontal. The ball leaves the pitcher's hand at a height of 5 feet. Find parametric equations that describe the motion of the ball as a function of time. How long is the ball in the air? When is the ball at its maximu

Set of 15 problems on gravitation.

1. Given the perihelion distance, aphelion distance and speed at perihelion of a planet, which of the following cannot be calculated? a) the mass of the start b) the mass of the planet c) the speed of the planet at aphelion d) the period of orbit e)the semimajor axis of the orbit 2. The mass density of a certain planet

force applied to the block and slab system

Please see attached file for full problem description. A 4.40-kg block is placed on top of a 5.50-kg slab. If the slab is held fixed, the block can be made to slip only if a minimum force of 12.0 N is applied to it. The assembly is now placed on a horizontal, frictionless surface, as shown in the diagram. a) What is th