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5.3 How much do you weigh?
Opportunity is the Force of gravity
name of one of the You become familiar with the force of gravity from early childhood.
rovers that sent You pick up objects and when you drop them, they fall to the ground.
amazing images Fruit falls from the trees; objects thrown horizontally eventually fall back
textbooks nis edu kz
back from Mars. down; if we jump up, we always land again.
When moving a rock We explain this phenomenon of objects coming back down to Earth as
on Mars to study it, the force of gravity. Gravity is a force that causes all things with mass
Opportunity uses a lot to gravitate (move) towards each other. The Earth has a very large mass,
so it attracts all the objects near it: houses, people, animals, birds, water
less force than it would
in oceans, seas and rivers, the Moon and even artificial satellites.
need to move a similar-
sized rock on Earth. REMEMBER! The force that attracts all objects to the Earth is called the
Why do you think force of gravity. The force with which an object acts on a support (or
that is? stretches the suspension that prevents the object from falling down) is
called the weight of the object.
w = mg
weight = mass · gravity
The force of gravity can be calculated using the formula:
force of gravity = mass of the object · gravitational acceleration
on Earth
F gravity = m · g
Force of gravity F is measured in newtons (N). To calculate the
gravity
Opportunity rover leaving its force of gravity acting on the object of any mass, the mass m (in kg)
lander on Mars is multiplied by the gravitational acceleration g. The gravitational
acceleration on the Earth is
N
g = 9.81
kg
True colour panoramic image of the Spirit of St. Louis crater on the
surface of Mars. Image taken by a panoramic camera on the Opportunity
Rover, in March 2015.
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