Physics- Gravitational Fields

Description

Physics Unit 4 Flashcards on Physics- Gravitational Fields, created by sammy414 on 26/11/2013.
sammy414
Flashcards by sammy414, updated more than 1 year ago
sammy414
Created by sammy414 almost 11 years ago
42
1

Resource summary

Question Answer
What will experience an attractive force when placed in a gravitational field? Any object with mass
What will an increase in mass have on the gravitational force? The force will also increase
What objects have a significant gravitational effect here on earth? The moon and the sun- They cause our tides
What do gravitational field lines show? The direction of the force that masses would feel in a gravitational field
If you put a small mass anywhere in the Earths gravitational field where would it be attracted to? The earth
What type of gravitational field is the earth? Far away: Radial Close to the earths surface: Uniform
If you move a mass further away from the earth what effect will this have on the force it experiences? It will decrease
The force experienced by an object in a gravitational field is always ... Attractive and a vector quantity
What do vector quantities depend on? The masses involved and the distances between them
What does Newtons Law of gravitation calculate? The force experienced between two masses
What type of law is the Newtons law of gravitation? An inverse law
In Newtons law of gravitation, if the distance between the masses increases then the force will ... decrease
In Newtons law of gravitation, if the distance doubles then the force will ... be one quarter the strength of the original force
What is field strength defined as? The force per unit of mass
What does the gravitational field strength depend on? Where you are in the field
What are the units for Gravitational field strength? Nkg^-1
What type of quantity is 'g' Gravitational field strength? Vector- always pointing towards the centre of the mass
What can we assume 'g' is at the earths surface? a constant called acceleration due to gravity because the field is uniform
What type of field do point masses have? Radial
In a radial field g is ... inversely proportional to r^2
What does a graph of g against r for the earth look like?
What does the area under a 'g' against 'r' graph find? The gravitational potential
What is gravitational potential defined as? Potential energy per unit mass
What are the units for gravitational potential ? Jkg^-1
Is gravitational potential positive or negative on the surface of the mass? Negative and increases with distance
What will the gravitational potential be at an infinite distance from the mass? Zero
How would a graph look for Gravitational potential varying with distance?
What does the gradient find of a Gravitational potential against distance graph? The value of g at that point
What is gravitational potential difference? The energy needed to move a unit of mass
How are planets and orbits kept in orbit? By the gravitational forces
What keeps any object that is undergoing circular motion in its path? A centripetal force
What does the force depend on? Give an example of this? It depends on the object In satellites its the gravitational attraction of the mass there orbiting
What must the gravitational and centripetal forces equal? Each other
What is the time taken for a satellite to make one orbit called? The orbital period
The greater the radius of a satellites orbit ... The slower it will travel and the longer it will take to complete one orbit
The energy of an orbiting satellite ... Is constant
What energies does an orbiting satellite have? Kinetic and potential energy
In a circular orbit a satellites speed and distance are ... constant; so the kinetic energy and potential energy are also constant
In an elliptical orbit when will a satellite speed up? When its height decreases
In an elliptical orbit when the kinetic energy increases... The potential energy decreases
What do geosynchronous satellites do? orbit directly over the equator and are always above the same point on the earth
What speed does a geosynchronous satellite travel at? the same angular speed as the earth below
What are geosynchronous satellites useful for and why? Sending TV and telephone signals- the satellite is stationary, so don't need to move the angle of your receiver
How long is a geosynchronous orbit? Exactly one day
Show full summary Hide full summary

Similar

The Liberal Reforms
Louisa Wania
AQA Psychological Approaches
Zoe Jervis
A Hero revision flashcards
Sarah Holmes
Veronica revision mindmap
Sarah Holmes
Symbolism in Veronica
Sarah Holmes
The Vietnam War
Iona Diack
ENGLISH LIT GCSE PAPER 2 revision
Emily gates
Chemistry Paper 2
Paige Snowling
GCSE Edexcel RE Paper 1 and 2 Quiz
Kerris Linney
Social Policy
Izzy Collinson
A-Level Psychology AQA Paper 2
Naomi Buck