A rock is thrown upward from ground level with initial velocity Vo, beside a building whose roof height is H. In terms of Vo, H and g, find what percent of its total flight time the rock is above the roofline.
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.
A 12.0-kg box rests on the flat floor of a truck. The coefficients of friction between the box and the floor are s=0.19 and k=0.15. The truck stops at a stop sign, and then begins to move with an acceleration of 2.20 m/s^2 . If the box is 1.80 m from the rear of the truck when the truck starts, (a) How much tim
Angular acceleration, tangential speed, and angle turned, in radians, by a flywheel of known diameter.
A flywheel whose diameter D= 1.2 m, is initially rotating at Wo= 200 revolutions per minute. During time t- 60 sec, its rotation rate increases with constant acceleration to a final value of Wf= 1000 rev/min. Part a. find the initial tangential speed in m/sec, of a point on the rim. Part b. find the angular acceleration in ra
I need help with the following two questions. Please view the attachments to see the questions.
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
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
Please see the attachment. What is the most straight forward way to solve it? Please provide explanations for the major steps. Thanks.
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.
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
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
A Ferris wheel rotates at an angular velocity of 0.24 rad/s. Starting from rest, it reaches its operating speed with an average angular acceleration of 0.030 rad/s^2. How long does it take the wheel to come up to operating speed?
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
A 2500 kg car traveling to the north is slowed down uniformly from an initial velocity of 20.0 m/s by a 6250 N braking force acting opposite the car's motion. Use the impulse-momentum theorem to answer the following questions: a. What is the car's velocity after 2.50 s? b. How far does the car move during 2.50 s? c. How
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
A disk starts from rest and accelerates at constant angular acceleration to 10 rev/sec in time t. While rotating through the next 60 revolutions, its speed increases to 15 rev/sec. Part a. Find the angular acceleration in rad/sec^2. Part b. Find T, the time required from 10 to 15 rev/sec.
Child stands on frozen pond: Determine the minimum time required for the child to walk to shore without slipping
A child stands on the surface of a frozen pond 12 m from the shore. If the coefficient of static friction between her boots and the ice is 0.05, A. Determine the minimum time required for the child to walk to shore without slipping.
Angular acceleration of a mass attached to a 59.7 cm long string starting from rest and rotated 32 times.
A mass attached to a 59.7 cm long string starts from rest and is rotated 32 times in 68.0 s before reaching a final angular speed. Determine the angular acceleration of the mass, assuming that it is constant.
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.
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.
A 15kg box sits on a table. It is not moving. Please answer the following questions and show your work if possible. The force of gravity is equal to __Newtons. The force of the table against the box is the ___force. The force of the box against the table is equal to ___Newtons.
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
An airplane has a mass of 3.1 x 10^4 kg and takes off under the influence of a constant net force of 3.7 x 10^4 N. What is the net force that acts on the plane's 78-kg pilot?
A roller coaster car of mass 320 kilograms(including passengers) travels around a horizontal curve of radius 35 meters. Its speed is 16 meters per second. What is the magnitude and direction of the total force exerted on the car by the track?
A 1500kg car drives around a flat curve with a radius of 52m the car has an acceleration of 52m/s^2. What is the maximum force needed so the car will not slip?
1) A car starts from rest with an acceleration of 6 m/sec2. After attaining a speed of 30 m/sec it maintains a constant speed. Find (a) the distance traveled in 10 seconds and (b) average speed during in the first 10 seconds. 2) A projectile is fired from the ground with an unknown speed at an angle fo 30 degrees. Its rang
A pulley with one end connected to a 300 gm block and the other connected to an unknown weight(M) has a negligible friction. The tension in the string is given as 2 nt. Determine: (a) the acceleration of the 300 gm block. (b) the force acting on the 300 gm block. (c) weight of M in Newton's (d) value of the unknown ma
From the attached diagram, determine (a) frictional force (b) acceleration of the system (c) tension in the string (d) net force acting on the 2 dg block. The coefficient of friction is 0.4.
"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
"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