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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 ############################

Calculating with 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-sk

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

Acceleration Problem - Equation of Motion

Figure 1-43 shows two blocks, each of mass m, suspended from the ends of a rigid weightless rod of length L1+L2 with L1 = 19 cm and L2 = 82 cm (see attachment). The rod is held horizontally on the fulcrum and then released. (a) What is the magnitude of the initial acceleration of the block closer to the fulcrum. (b) What is

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

Center Mass Problem

Question: A 60-kg woman leaps vertically from a crouching position in which her center of mass is 30 cm above the ground. As her feet leave the floor her center of mass is 62 cm above the ground; it rises to 105 cm at the top of her leap. - What average force was exerted on her by the ground during the jump? - What maximum s

Calculating Angular Acceleration and Revolutions

Question: The blades of a fan running at low speed turn at 250 rpm. When the fan is switched to high speed, the rotation rate increases uniformly to 350 rpm in 5.75 s. a.) What is the magnitude of the angular acceleration of the blades? b.) How many revolutions do the blades go through while the fan is accelerating?

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.

Determining Work Done by Forces

A 500-kg helicopter ascends from the ground with an acceleration of 2.00m/s^2. Over a 5.00 seconds interval, what is (a) the work done by lifting force, (b) the work done by the gravitational force, and (c) the new work done on the helicopter?

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

Force applied to pushing a crate.

A 1000 newton crate is being pushed across a level floor at a constant speed by a force of 300 newtons at an angle of 20 degrees below the horizontal A-what is the coeffecient of kinetic friction between the crate and the floor. B-if the 300 newton force is instead of pulling the block at an angle of 20 degrees above the hori

Magnitude of acceleration of the block after system is released

A uniform, solid cylinder with mass M and radius 2R rests on a horizontal tabletop. A string is attached by a yoke to a frictionless axle through the center of the cylinder so that the cylinder can rotate about the axle. The string runs over a disk shaped pulley with mass M and radis R that is mounted on a frictionless axle th

Dynamics of rotational motion: Atwoods machine

Atwoods Machine Two blocks, A and B are attached to each end of a cord attached to a pulley C. Block A hangs slightly higher than Block B. Find the linear accelerations of block A and B, and the angular acceleration of the wheel C and the tension in each side of the cord if there is no slipping between the cord and the surf

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

Second Law of Motion: Magnitude and Direction of Acceleration

A boat has a mass of 6800 kg. Its engines generate a drive force of 4100 N, due west,while the wind exerts a force of 800 N, due east, and the water exerts a resistive force of 1200 N due east. What is the magnitude and direction of the boats acceleration?

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.