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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

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

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

Mechanics / Rocket

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 rockets trajectory starting f

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

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

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

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