Table of Contents
- 1 Does perpetual motion work in a vacuum?
- 2 Would you expect tides to be higher at the equator or at the North Pole Why?
- 3 Does friction work in a vacuum?
- 4 When a rigid object rotates about a fixed axis all the points of the object have the same tangential speed?
- 5 What is the minimum escape velocity of a parabolic orbit?
- 6 What are the motion characteristics of a satellite moving in ellipse?
Does perpetual motion work in a vacuum?
There are two kinds of perpetual motion: Motion with zero-friction. This can and does exist in vacuum and in atoms and electrons, etc. Motion that produces net work or more energy than it starts with, without any external source of energy.
When a wheel rotates about a fixed axis do all the points on the wheel have the same tangential speed?
No, only points with equal distance from the center will have the same tangential speed, but points that have different distances from the center will have different tangential speeds.
Would you expect tides to be higher at the equator or at the North Pole Why?
F = G M m /r2. But since the Earth is rotating,the radius of the Earth is larger near the equator than near the poles, so the force of gravity at the equator would be less than at the poles. If you add into this situation the effect of tides caused by the moon and sun, the difference can become a little larger.
What is a perpetual vacuum?
A perpetual motion machine is a hypothetical machine that can do work infinitely without an external energy source. Thus, machines that extract energy from finite sources will not operate indefinitely, because they are driven by the energy stored in the source, which will eventually be exhausted.
Does friction work in a vacuum?
The results seemed to go against the laws of physics: The vacuum, by definition, is completely empty space and does not exert friction on objects within it. As a decaying atom moves through the vacuum, it really does experience some kind of force resembling friction.
When an object rotates about a fixed axis What is true about all points in the object?
When a rigid object rotates about a fixed axis, what is true about all the points in the object? (There could be more than one correct choice.) They all have the same angular acceleration. They all have the same angular speed. Two children, Ahmed and Jacques, ride on a merry-go-round.
When a rigid object rotates about a fixed axis all the points of the object have the same tangential speed?
When a rigid body rotates about a fixed axis all the points in the body have the same angular speed. When a rigid body rotates about a fixed axis all the points in the body have the same tangential speed. When a rigid body rotates about a fixed axis all the points in the body have the same centripetal acceleration.
Is it possible to stand still in space?
There’s no such thing as a standstill, period. An object can only be at a standstill relative to some specific other object. Everything in space is moving in different directions and speeds. You can be orbiting Earth at a standstill relative to a point on Earth’s surface, called a geosynchronous orbit.
What is the minimum escape velocity of a parabolic orbit?
Hence, the equation for parabolic orbital velocity will give the minimum escape velocity of 11.2 km/sec. r k V 22 Problem 1 •Calculate the velocity of an artificial satellite orbiting the Earth in a circular orbit at an altitude of 200 km above the Earth’s surface.
What is the speed of a satellite in orbit around Earth?
If shot with a speed greater than 8000 m/s, it would orbit the earth in an elliptical path. The motion of an orbiting satellite can be described by the same motion characteristics as any object in circular motion. The velocity of the satellite would be directed tangent to the circle at every point along its path.
What are the motion characteristics of a satellite moving in ellipse?
Similar motion characteristics apply for satellites moving in elliptical paths. The velocity of the satellite is directed tangent to the ellipse. The acceleration of the satellite is directed towards the focus of the ellipse.
What is the eccentricity of a satellite’s orbit?
Sample Satellite Orbits •The orbit of a satellite launched by the simple means of pushing it out of the bay of the Space Shuttle would have Orbital period 90 minutes, semi-major axis about 6500 km •The motion of a spacecraft that is always located over the same part of the Earth would have Semi-major axis 22,000 miles (35,000 km), eccentricity 0