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Angular Momentum and Centripetal Force

A car of mass 1000kg moves with a speed of 50 m/s on a circular track of radius 100m. What is the magnitude of its angular momentum (in kg.m^2/s) relative to the center of the racetrack? ============================================== Answers: a) 5 x 10^2 b) 5 x 10^6 c) 2.5 x 10^6 d) 2.5 x 10^4 ############################

Calculations Using Newton's 2nd Law

1. A ball that weights 5N falls on earth ...what is the net force that acts on the ball during the fall? Which is the force (including its direction) that the ball exercises on the land when it falls? 2. In the moon, the gravitational acceleration of the objects is around 1.67 meter/s2 How much does it weight in the moon an ob

Force, Newton's 2nd law

1. If a cord is pulled upward, making an angle of 27º with respect to the horizon line, produces a force of 365N and can pull a box over the floor with a weight of 55.2 kg at a constant speed of 20.5 centimeters/sec - which is the magnitude of the friction force that opposes the movement of the box? 2. A boat pulls a water-ski

Calculus : Acceleration, Average Value and Values of Derivatives

8) The acceleration at time t, of a particle moving along the x axis is given by a(t)=20t^3+6. At time t=0 the velocity of the particle is 0 and the position of the particle is 7. What is the position of the particle at time t? 12) The function f is given by f(x)=3x^2+1. What is the average value os f over the closed inte

Inertia problem

In Fig. 11-42, one block has a mass M = 500 g, the other has mass m = 460 g, and the pulley, which is mounted in horizontal frictionless bearings, has a radius of 5.00 cm. When released from rest, the heavier block falls 81.5 cm in 2.90 s (without the cord slipping on the pulley). (a) What is the magnitude of the block's acce

Coriolis Acceleration Physics

Question: Pin P is attached to the collar shown; the motion of the pin is guided by a slot cut in bar BD and by the collar that slides on rod AE. Rod AE rotates with a constant angular velocity of 5 rad/s clockwise and the distance from A to P increases at a constant rate of 2 m/s. Determine at the instant shown (a) the angular

Uniform Circular Motion and Angular Speed

Question: A rotating cylinder about 16 km in length and 8.0 km in diameter, is designed to be used as a space colony. With what angular speed must it rotate so that the residents on it will experience the same acceleration due to gravity on Earth?

Calculating Acceleration

Question: Bar BDE is attached to two links AB and CD. Knowing that at the instant shown link AB rotates with a constant angular velocity of 3 rad/s clockwise, determine the acceleration (a) of point D, (b) of point E. Please refer to attachment to see a diagram of this scenario.

What force must be applied to the wedge?

Cam mechanisms are used in many machines. For example, cams open and close the valves in your car engine to admit gasoline vapor to each cylinder and to allow the escape of exhaust. The sliding wedge duplicates the function of a rotating eccentric disk on a camshaft of your car. Assume there is no friction between the wedge and

Rocket Problem

A test rocket is fired vertically from a well. A catapult boosts it to ground level, where it has a vertical velocity of 60.0 m/s. At ground level, the rocket engine fires, and the rocket accelerate upward with an acceleration of 5.00 m/s2. When the rocket is 800 m above the ground the engine fails, and the rocket goes into fr

Position of Particle Equation

The position of a particle which moves along a straight line is defined by: x=t^3-6t^2-15t+40, where x is in feet and t is in seconds. Determine the time at which the velocity will be zero, the position and distance traveled at that time, and the acceleration of the particle at that time.

Velocity and Acceleration of a Pack

To protect his food from hungry bears, a boy scout raises his food pack with a rope that is thrown over a tree limb at height h above his hands. He walks away from the vertical rope with a constant velocity, vboy, holding the free end of the rope in his hands. a) Show that the speed v of the food pack is given by x(x^2+h^2)^(-1

Centripetal Acceleration and Tangential Acceleration

A centrifuge is used for training astronaunts to withstand large accelerations. It consists of a chamber (in which the astronaunt sits) that is fixed to the end of a long horizontal and rigid pole. The arrangement is rotated about an axis perpendicular to the pole's free end. Such a centrifuge starts from rest and has an angular

Angular acceleration

In a pulley system, the time of descent of a 100 gram mass is found to be 35 seconds. The vertical distance is given as 120 cms. The radius of the pulley (in the form of a disc) is 5 cms. Mass of the pulley is unknown. Determine (a) angular acceleration of the pulley (b) number of revolutions it makes during this time (c) To

Angular acceleration of a rod at the moment of release

See attached file for diagram. A uniform rod of mass M = 5.18 kg and length L = 1.20 m can pivot freely (i.e., we ignore friction) about a hinge attached to a wall, as seen in the figure attached in a Word doc. The rod is held horizontally and then released. Determine the angular acceleration of the rod at the moment of relea

Angular acceleration

Q: "The blades in a blender rotate at a rate of 7290 rpm. When the motor is turned off during operation, the blades slow to rest in 3.67 s. What is the angular acceleration as the blades slow down? The initial rotation is in the positive direction." The OTA's solution is attached. We both got an answer of 208 rad/s^2.

Rpm and Angular Acceleration

Question: The blades in a blender rotate at a rate of 7290 rpm. When the motor is turned off during operation, the blades slow to rest in 3.67 s. What is the angular acceleration as the blades slow down? The initial rotation is in the positive direction.

Normal Force, Static and Kinetic Frictional Forces For A Cup Of Coffee

A cup of coffee is setting on a table in a airplane that is flying at a constant altitude and a constant velocity. The coefficient of the static friction between the cup and the table is 0.30. Suddenly, the plane accelerates, its altitude remaining constant. What is the maximum acceleration that the plane can have without the cu

Constant Acceleration Factors

"A runner hopes to complete the 10,000-m run in less than 30.0 minutes. After exactly 27.0 minutes, there are still 1100 m to go. The runner must then accelerate at 0.20 m/s^2 for how many seconds in order to achieve the desired time?" Here's what I've done: So far, the runner has gone 8900 m in 1620 s, which should give h

Simple conversion

"A sprinter accelerates from rest to 10.0 m/s in 1.35 seconds. What is her acceleration in (a) m/s^2, and (b) km/h^2?" I got (a) right. Acceleration = 10/1.35 = 7.41 m/s^2. But I somehow screw it up when I go to do the conversion. Here's what I did: 10 m = 0.01 km 1.35 s = 3.75 x 10^-4 hr (1.35 x (1 hr/3600 s) So the s

Force, acceleration, coefficient of kinetic friction

See attached file for the graph. In the figure below, m1 = 10.7 kg and m2 = 4.15 kg. The coefficient of kinetic friction is 0.271. If the system is set in motion with m2 moving downward, what will be the acceleration of the system? I'm not sure how to factor in the coefficient of kinetic friction. Can you show me how to do

Vectors and distance: How far in advance must rescue aircraft drop supplies

See attached drawing in Word file. Please give me a step by step rundown of how to do it? "A rescue plane wants to drop supplies to isolated mountain climbers on a rocky ridge H = 227 m below. If the plane is traveling horizontally with a speed of 223 km/hr (61.9 m/s), how far in advance of the recipients (horizontal dista

Acceleration of freight train: Time for fugitive

"A fugitive tries to catch a freight train traveling at a constant speed of 5.95 m/s. Just as an empty box car passes him, the fugitive starts from rest and accelerates at 3.84 m/s^2 to his maximum speed of 8.23 m/s. How long does it take him to reach the empty box car?"