Energy of a Spacecraft (Energy; Gravitational Force; Speed)

Very far from earth (at {see attachment}), a spacecraft has run out of fuel and its kinetic energy is zero. If only the gravitational force of the earth were to act on it (i.e., neglect the forces from the sun and other solar system objects), the spacecraft would eventually crash into the earth. The mass of the earth is Me and i ...continues

Problem 12.42

Please do not place your response in a .pdf format, but Word documents are okay. Thanks! Two meteoroids are heading for earth. Their speeds as they cross the moon's orbit are 2.0 km/s. (A) The first meteoroid is heading straight for earth. What is its speed of impact? Make sure your answer is in km/s. (B) The second mi ...continues

Elliptical Orbit (Speed; Distance)

Mercury moves in a fairly elliptical orbit around the sun. Mercury's speed is 38.8 km/s when it is at its most distant point, 6.99*10^9 m from the sun. (A) How far is Mercury from the sun at its closest point, where its speed is 59.0 km/s? Your answer should be in meters.

Rotational Dynamics / Kinetmatics (Moment of Inertia; Newton's Second Law; Parallel-Axis Theorem; Angular Velocity)

A uniform board of mass m and length L is pivoted on one end and is supported in the horizontal position by a rope attached to the other end. Another rope, attached to the board a distance L/3 from the pivot point, is being pulled straight down with a constant force of magnitude F. Suddenly, the rope attached to the end of the ...continues

Problem Solving: Equilbrium of Rigid Bodies (Net Force; Net Torque; Pivot Point)

A horizontal uniform bar of mass m and length L is hung horizontally on two vertical strings. String 1 is attached to the end of the bar and string 2 is attached a distance L/4 from the other end. A monkey of mass m/2 walks from one end of the bar to the other. Find the tension T1 in string 1 at the moment that the monkey is hal ...continues

Friction Force (Spinning Disk)

The 3.20-kg, 38.0-cm diameter disk in the figure is spinning at 350 rpm. A. How much friction force must the brake apply to the rim to bring the disk to a halt in 2.40 seconds? *Please see attachment for diagram

Unwinding Cylinder (Moment of Inertia; Angular Rotation; Velocity of Center of Mass; Positive Linear Velocity)

A cylinder with moment of inertia I about its center of mass, mass m, and radius r has a string wrapped around it which is tied to the ceiling. The cylinder's vertical position as a function of time is y(t). At time t=0 the cylinder is released from rest at a height h above the ground. **Please see attachment for complete q ...continues

Pulling a String Adds Energy to a Wheel (Moment of Inertia; Angular Velocity; Final Rotational Speed; Instantaneous Power Delivered)

A bicycle wheel is mounted on a fixed, frictionless axle, with a light string wound around its rim. The wheel has moment of inertia I=kmr[squared], where m is its mass, r is its radius, and k is a dimensionless number between zero and one. The wheel is rotating counterclockwise with angular velocity Wo, when at time t=0 someone ...continues

Problem 13.74

Please do not put your response in a .pdf format, but Word documents are okay. Thanks! A long, thin rod of mass M and length L is standing straight up on a table. Its lower end rotates on a frictionless pivot. A very slight push causes the rod to fall over. (A) As it hits the table, what is the angular velocity of the tip ...continues

Radioactive Decay. I request the OTA # 104557 Morris (David) Roth. Thank you.

I can use up to 3 credits. Instructions: Please fill in the blanks; answer all questions. Also, explain how you reached every answer in SIMPLIST form. Radioactive Decay Carbon-14 is a radioactive Isotope of Carbon-12. How many protons and neutrons are in the nucleus of C-12? __________ In C-14 ___________ While an o ...continues