1) 29.4 N
The force of gravity between two objects is given by:
where
G is the gravitational constant
M and m are the masses of the two objects
r is the separation between the centres of mass of the two objects
In this problem, we have
(mass of the Earth)
(mass of the box)
(Earth's radius, which is also the distance between the centres of mass of the two objects, since the box is located at Earth's surface)
Substituting into the equation, we find F:
2) 
Let's now calculate the ratio F/m. We have:
F = 29.4 N
m = 3.0 kg
Subsituting, we find
This is called acceleration of gravity, and it is the acceleration at which every object falls near the Earth's surface. It is indicated with the symbol 
.
We can prove that this is the acceleration of the object: in fact, according to Newton's second law,
where a is the acceleration of the object. Re-arranging,
which is exactly equal to the quantity we have calculated above.
Answer:
Velocity = 0.0001389 m/s
Explanation:
Given that the
Distance covered = 1 metre
Time taken = 2 hours
Convert the hour to second
1 hour = 60 × 60 = 3600
2 hours = 2 × 3600 = 7200
What is the velocity of a worm moving 1 meter in 2 hours to the East?
Velocity can be referred as speed.
Velocity = distance/ time
Velocity = 1/7200
Velocity = 0.0001389 m/s
<h2>
Answer: Invariance of the speed of light in vacuum </h2>
Special relativity was proposed on 1905 by Einstein, who developed his theory based on the following two postulates:
<em>1. The laws of physics are the same in all inertial systems. There is no preferential system. </em>
<em>2. The speed of light in vacuum has the same value for all inertial systems. </em>
<em></em>
Focusing on the first postulate, it can be affirmed that any measurement on a body is made with reference to the system in which it is being measured.
In addition, it deals with the <u>dilation of time</u> stating that <u>time passes at different rates in regions of different gravitational potential</u>. That is, the greater the local distortion of space-time due to gravity, the slower the time passes.
On the other hand, following what relativity establishes, bodies within a gravitational field follow a curved space path.
