Spacecraft orbiting -- need to find the period

A spacecraft is in orbit around Jupiter. The radius of the orbit is 3.0 times the radius of Jupiter (RJupiter = 71,500 km). The gravitational acceleration at the surface of Jupiter (the surface is defined as the above radius) is 23 m/s2. Without using any other information about Jupiter, what is the period of the spacecraft's ...continues

Block Sliding down a frictionless plane at an angle

A 4.0 kg block is released from rest at the top of a frictionless plane of length 8.0 m that is inclined at an angle of 15° to the horizontal. A cord is attached to the block and trails along behind (assume the cord is massless). When the block reaches a point 5.0 m along the incline from the top, someone grasps the cord and ...continues

Rotation problems

1. At t=0, a fly wheel has an angular velocity of 4.7 rad/s (radians per second), an angular acceleration of -0.25 rad/s^2 , and a reference line at pheta0 = 0. (a) Through what maximum angle phetamax will the reference line turn in the positive direction ? At what times t will the reference line be at (b) pheta = 1/2phetamax an ...continues

Find Kinetic energy of earth due to its rotation about its axis.

Assume the Earth is a uniform solid sphere. Find the kinetic energy of the Earth due to its rotation about its axis. Suppose we could somehow extract 1.0% of the Earth's rotational kinetic energy to use for human needs. By how much would that change the length of the day? For how many years would 1.0% of the Earth's rotation ...continues

Ball rolling down in incline, then through a loop to loop -- find speed neccesary to complete the loop.

A solid steel ball of radius r rolls down an incline into a loop-the-loop of radius R. What is the minimum speed the ball must have at the top of the loop in order to stay on the track? At what vertical height on the incline, in terms of the radius of the loop, must the ball be released in order for it to have the required min ...continues

Force of friction

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.

Friction

You push on a 25kg box with a force of 400 Newtons. There is 250 Newtons of friction. Please answer the following questions and show your work if possible. What is the net force in the x direction? What is the acceleration of the box? If friction were 200 Newtons, what action force would need to be applied to have c ...continues

friction

A 25kg box sits on a ramp that is slanted 30 degress. It is not moving. Please answer the following questions and show the formula and work if possible. What is the x component of the weight along the ramp? What is the y component of the weight perpendicular to the ramp?

Body water question

Assume that the human body is 75% water. How many moles of water are in your body? How many molecules? If I am 75% water, then why am I always getting thirsty? My body weight is 165lbs.

Ultraviolet light problem

Certain crystals fluoresce when exposed to a short burst of ultraviolet light. The amount of light emitted by the crystals is both time and temperature dependent. The emitted light is maximum at the time of excitation, the output then decaying with time. Such materials can be used to measure temperature. Given are some relative ...continues