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Velocity

Circular Motion

In uniform circular motion, the acceleration is perpendicular to the velocity at every instant. Is this true when the motion is not uniform, that is, when the speed is not constant?

Circular Motion in Cycling

Dan and Beatrice cycle side by side. The tires on Dan's bike are large in diameter than those on Beatrice's bike. Which wheels, if either, have the greater rotational speed? Explain.

The Velocity of a Rocket at Parigee of an Elleptic Orbit

Problem # 4 - The rocket is traveling in a free-flight elliptical orbit about the earth such that e = 0.76 and Its perigee is 9Mm as shown. Determine its speed when it is at point B. Also determine the sudden decrease in speed the rocket must experience at A in order to travel in a Circular orbit about the earth.

Two Particle system in inertial frames, and Newtonian Relativity.

The question starts, Consider an isolated system comprising two particles of masses m1 and m2. Whose position vectors, in an inertial frame, are x1 and x2 and whose velocity vectors are v1 and v2. The interaction of the particles may be described by an energy function. E=1/2m1v1^2+1/2m2v2^2+U(x1,x2) i) Which aspect of

Positve and Negative Acceleration and Velocity

1. Discuss the validity of each of the following statements. Provide examples to support the answers. a) If the acceleration of an object is positive, it is speeding up. If the acceleration of an object is negative, it is slowing down. b) If the velocity of an object is positive, it is moving away from the origin. If the vel

Electric Current: Velocity of electron in a beam; Current of a beam

In a certain electron beam, there are 5.0 x 10^6 electrons per cubic centimeter. Suppose the kinetic energy of each electron is 10 keV and the beam is cylindrical with a diameter of 1 mm. (a) what is the velocity of an electron in the beam? (b) find the beam current.

Average Velocity of a Particle

The position of a particle as a function of time is given by x(t) = (3.1 m/s)t - (4.2 m/s^2)t^2. What is the average velocity of the particle between t = 1.0 s and t = 2.0 s?

Speed of Baseball Player

A baseball player is running to second base at 5.63 m/s. When he is 5.20 m from the plate he goes into a slide. The coefficient of kinetic friction between the player and the ground is 0.220. What is his speed when he reaches the plate? 4.47 m/s 3.04 m/s 1.96 m/s He stops before reaching the plate.

Value of angle x

A ball is thrown with a velocity of 40 m/s at an angle x above the horizontal. If the ball attains its maximum range, what was the value of the angle x?

Vertical Component of Velocity at Highest Point

A boy kicks a football with an initial velocity of 20 m/s at an angle of 30 degrees above the horizontal. What is the vertical component of its velocity at the highest point of its trajectory?

Horizontal component of velocity

A girl kicks a soccer ball with an initial velocity of 25 m/s at angle of 30 degrees above the horizontal. The horizontal component of the velocity of the ball is described by which of the following statements: It changes uniformly. It is zero. It is 25 m/s. It remains constant during the ball's flight.

Velocity and Acceleration

A car travels along east and its velocity decreases. The acceleration of the car is in which direction (northward, eastward, southward, or westward)? Explain.

Projectile Motion with a Baseball

A baseball thrown at an angle of 60 degrees above the horizontal strikes a building 20m away at a point 8m above the point from which it is thrown. Ignoring air resistance. Find A) the magnitude of the initial velocity of the baseball and B) the time it takes to reach the point.

Final velocity of baggage carrier

In problem 14.3(a), if the velocity of the 30 lb and 40 lb suit cases are 12 ft/s and 5 ft/s, respectively, when the first suit case of 30 lb was tossed into the carrier, the final velocity of the baggage carrier after the second baggage tossed into the carrier is: a. 4.25 ft/s b. 4.67 ft/s c. 3.87 ft/s d. 5.67 ft/s

Cliff of the height calculation

A diver running 2.1 m/s dives out horizontally from the edge of a vertical cliff and reaches the water below 3.0s later. How high was the cliff and how far from its base did the diver hit the water?

Bullet's Projectile Motion

A gun fires a bullet at 250 m/s at a 45 degree angle with the horizontal. How far away from the point of launch will the bullet fall? And how much time will the bullet stay up in the air?

Simple Harmonic Motion

See attached file for full problem description. 1. Gina's favorite exercise equipment at the gym consists of various springs. In one exercise, she pulls a handle grip attached to the free end of a spring to 0.80 m from its unstrained position. The other end of the spring is held in place by the equipment frame. What is the magn

Newton's 2nd Law - Kinetics

Dynamics 12.8 A car has been traveling up along a 2 percent grade at a constant speed of 55 miles/hr. If the driver does not change the setting of the throttle or shift gears as the car reaches the top of the hill, what will be the acceleration of the car as it starts moving down the 3 percent grade? Dynamics 13.7 A 24-

Orbital Mechanics

A lunar landing craft needs to hover just above the surface of the moon, which has a gravitational acceleration of (1/6) g. The exhaust velocity is 2000m/s but fuel amounting to only 20% of the total mass can be used. How long can the landing craft hover?

Energy Questions

1) Find the curl, delta x F, for the following forces: (a) F = kr; (b) F = (Ax, By2, Cz3); (c) F = (Ay2, Bx, Cz), where A, B, C and k are constants. 2) Verify that the gravitational force - GMmr/r2 on a point mass m at r, due to a fixed point mass M at the origin, is conservative and calculate the corresponding potent

Rotationial kinematics

A basketball player is balancing a spinning basketball on the tip of his finger. The angular velocity of the ball slows down from 18.5 to 14.1 rad/s. During the slow-down, the angular displacement is 85.1 rad. What is the time it takes for the ball to slow down?

Calculations with Angular Velocity

A floor polisher has a rotating disk with a radius of 15 cm. The disk rotates at a constant angular velocity of 1.4 rev/s and is covered with a soft material that does the polishing. An operator holds the polisher in one place for 45s in order to buff an especially scuffed area of the floor. How far (in meters) does a spot on th

Radiological Physics Questions

1. Dennis Chapman did not eat for a few days and went to a restaurant which says buffet all you can eat just $4.95. Dennis was so happy that he started eating and eating till the owner of the restaurant asked Dennis "May I help you sir?". Dennis said yes, just go away and let me eat. After eating Dennis weight from 185 lb becam

Areal Velocity and Time Averages

Question: Show that the areal velocity is constant for a particle moving under the influence of an attractive force given by F(r) = -kr. Calculate the time averages of the kinetic and potential energies and compare the results of the viral theorem.

Falling Objects on the Earth and Moon

Imagine that you are sitting on top of a 10-meter tower and drop two objects: a $20 gold piece (weight = 33g, diameter = 34mm) and a silver dollar (weight =26.7 g, diameter = 38mm). 1. Which, if either, falls faster? How do you support your answer? 2. If you repeated the same experiment on the Moon, what would you notice?

Recoil Velocity When Firing a Gun

The lead female character in a movie is standing at the edge of an offshore oil rig. As she fires a gun, she is driven back over the edge and into the sea. Suppose the mass of a bullet is 0.010 kg and its velocity is 720 m/s. Her mass (including the gun) is 51 kg. (a) what recoil velocity does she acquire in response to a si