What is the effect of gravity on a projectile?
Gravity causes a projectile to accelerate downwards towards the Earth.
What is the formula for weight?
W = mg, where W is weight in newtons, m is mass in kilograms, and g is gravitational field strength in N/kg.
What is the gravitational field strength on Earth?
9.8 N/kg.
How does gravitational field strength vary?
It varies from planet to planet and according to the distance from the planet’s center.
What is the gravitational field strength on the Moon?
1.6 N/kg.
What is an example of a projectile in orbit?
The International Space Station.
What happens to a satellite’s speed as its orbiting height increases?
The required forward speed decreases as the satellite is further from the Earth.
What was Sir Isaac Newton’s thought experiment about projectiles?
It involved firing a cannonball from a tall mountain to illustrate how increasing speed can lead to orbit.
What does Newton’s Law of Universal Gravitation state?
Every object with mass attracts every other object with mass.
What is the inverse square law in relation to gravity?
The gravitational force between two masses varies inversely with the square of the distance between them.
What is the formula for calculating gravitational attraction?
F = G(m1m2/r^2), where F is the force in newtons, G is the gravitational constant, m1 and m2 are the masses, and r is the distance between them.
What is the assumption made about large spherical masses in gravitational calculations?
They are regarded as point masses with all mass concentrated at their center.
What is the difference between G and g?
G is the universal gravitational constant; g is the gravitational field strength.
What does the gravitational field strength represent?
The force exerted on a unit mass.
How does the gravitational attraction of the Sun compare to that of the Earth?
The gravitational attraction of the Sun is imperceptible compared to that of the Earth.
What happens to the gravitational force if the distance between two objects doubles?
The gravitational force quarters.
What is the relationship between the altitude of a satellite and its speed?
Higher altitude results in lower orbital speed.
What is a practical example of a projectile?
Satellites in orbit around the Earth.
