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Masses, cord and pulley

A 4.78 kg mass (m2) is connected by a light cord to a 2.04 kg mass (m1) on a smooth surface. The pulley rotates about a frictionless axle and has a moment of inertia of 0.520 kg*m^2 and a radius of 0.350 m. 1.) Assuming that the cord does not slip on the pulley, find the acceleration of m1. 2.) What is the acceleration o

Average Angular Acceleration

Compact Disc. A compact disc (CD) stores music in a coded pattern of tiny pits 10^(- 7) m deep. The pits are arranged in a track that spirals outward toward the rim of the disc; the inner and outer radii of this spiral are 25.0 mm and 58.0 mm, respectively. As the disc spins inside a CD player, the track is scanned at a constant

Constant Acceleration Problem

Constant Acceleration Problem A motorist traveling with a constant velocity of 15 m/s passes a school-crossing corner. Just as the motorist passes, a police officer stopped on the corner starts off in pursuit with constant acceleration of 2.5 m/s^2 until her speed is 20 m/s. Then she slows down at a constant rate until she c

Potential Energy and Energy Conversion

Riding a Loop-the-loop. A car in an amusement park ride rolls without friction around the track shown in the figure. It starts from rest at point at a height above the bottom of the loop. Treat the car as a particle. 1. What is the minimum value of (in terms of) such that the car moves around the loop without falling off at t

Newton's Law (5.120)

(See attached file for full problem description with diagram). Moving Wedge. A wedge with mass rests on a frictionless horizontal table top. A block with mass is placed on the wedge (the figure a). There is no friction between the block and the wedge. The system is released from rest. 1. Calculate the acceleration of the

Concept of Psuedo Force

A 12.0-kg box rests on the flat floor of a truck. The coefficients of friction between the box and floor are : static = 0.19 and kinetic =0.15. The truck stops at a stop sign and then starts to move with an acceleration of 2.20 m/s^2. 1. If the box is 1.80 m from the rear of the truck when the truck starts, how much time elap

Newton's Law: Force, velocity, acceleration, and reaction.

A 4.9-N hammer head is stopped from an initial downward velocity of 3.2 m/s in a distance of 0.45 cm by a nail in a pine board. In addition to its weight, there is a 15-N downward force on the hammer head applied by the person using the hammer. Assume that the acceleration of the hammer head is constant while it is in contact wi

Newton's Second Law and Inclined Planes

(See attached file for full problem description with diagram and equations) --- The acceleration of a block of mass that is pulled up a frictionless plane inclined at angle with respect to the horizontal by a perfect string that passes over a perfect pulley to a block of mass that is hanging vertically. Visualize th

11 Newton's Laws Problems: Force, motion, acceleration, FBD,

Please solve each problem step by step giving solutions please. SHOW every equation used and every step getting to the answer. Show substitutions, etc. Please give units. Look below for pages. Adult student learning from ya'll and so you can read what I need help with I cut and paste the questions cause some cannot read m

Vertical Acceleration

A 5.5 kg object hangs at one end of a rope that is attached to a support on a railroad boxcar. When the car accelerates to the right, the rope makes an angle of 24 degrees with the vertical the acceleration of gravity is 9.8 m/s^2 : Find the acceleration of the car. (Hint: aobject = acar) Answer in units of m/s^2. Pictur

Uniform electric field: point charge and potential difference

Location A is 4 m to the LEFT of a point charge of 0.3 μC. Location B lies on the same line and is to the RIGHT of the charge. The potential difference VB - VA = 100 V. How far is Location B from the point charge? A uniform electric field has a magnitude of 2 x 103 N/C. In a vacuum, a proton begins with a speed of 4 x 1

Two Motion Questions

1. A truck initially traveling at 30 mph decelerates at 4 ft/s^2. Find (a) how long it takes to stop, (b) how far it moves in that time, and (c) how far the truck moves in the third second after the brakes are applied. 2. A boy throws a ball straight up from the top edge of a 50-ft building with a speed of 20 ft/s. How lon

Application of Bernoulli's theorem..

Problem 1 : Here is a cup with two holes (see attachment). The cup is filled with water to the top and the water is coming out of the holes. Assuming suitable values for heights, radius's etc. please answer the following questions : 1) Velocity with which the stream of water comes out. 2) Acceleration of the stream of w


Please answer each question with step by step solution please. Thanks! 1) A high speed sander has a disk of 9.11 cm in radius that rotates about its axis at a constant rate of 1170 rev/min. Find the angular speed of the disk in rad/sec. 2) Find the linear speed of a point 0.902cm from the disks center in m/s. 3) Find

Acceleration Calculation

A lunar lander is making its descent to Moon Base I. The lander descends slowly under the retro-thrust of its descent engine. The engine is cut off when the lander is 5.0 m above the surface and has a downward speed of 0.8 m/s. With the engine off, the lander is in free fall. What is the speed of the lander just before it to

Calculating acceleration and time of a jet

The catapult of the aircraft carrier USS Abraham Lincoln accelerates an F/A-18 Hornet jet fighter from rest to a takeoff speed of 173 mi/h in a distance of 307 ft. Assume constant acceleration. 1) Calculate the acceleration of the fighter in m/s2 2) Calculate the time required for the fighter to accelerate to takeoff speed

Motion in Plane: Rocket Lanching and Then Projectile Motion

See the attached file. A rocket accelerates upward from the ground at 25m.s-2 for 2.5s at an angle of 80o to the horizontal. The rocket motor stops and it eventually falls to the ground. Neglecting air resistance and assuming that the trajectory during acceleration is a straight line. a. Make a labeled sketch of the rocke

Calculating vertical displacement

See the attached file for the full problem description. Two basketball players are essentially equal in all respects (they are the same height, they jump with the same initial velocity, etc...). In particular, by jumping they can raise their centers of mass the same vertical distance, H (called their "vertical leap"). T

Velocity, acceleration, and constant speed

A motorcycle is following a car that is traveling at constant speed on a straight highway. Initially, the car and the motorcycle are both traveling at the same speed of 42.0 mph, and the distance between them is 60.0 m. After = 5.00 s, the motorcycle starts to accelerate at a rate of 8.00 m/s2. The motorcycle catches up with th

Projectile Motion of a Baseball Thrown

A teacher, 2.256 m tall, throws a basketball towards the hoop which is at a horizontal distance l. The basketball is thrown from the level of the teachers head or again 2.256 m at a velocity of 18 m/s, at an angle of 62 degrees from the horizontal. The height of the hoop 3.048 m. 1) Neglecting air friction, how long does

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)