Explanation :
According to astronomers, the whole universe is started with a giant explosion called as Big Bang. Big Bang theory shows that the universe is extended from high density state.
There are some evidence for big bang as :
(1) There are some red shifts of different galaxies which means that the universe is expanding.
(2) Due to the expanding of universe, some of the new elements are created like hydrogen, deuterium etc.
(3) Microwaves are detected by orbiting detectors.
All this parameters shows that big bang theory was correct.
Answer:
194,400 joules of kinetic energy.
Explanation:
Remember that to calculate the Kinetic energy you need to use the next formula:

We know that Mass= 1200 kg and velocity is 18m/s, so we insert those values into the formula:

So the kinetic energy of a car moving at 18m/s with a mass of 1200 kg would be 194,400 joules.
The planar simple harmonic wave travels in the positive direction of x axis with wave velocity u=2m/s, and the vibration curve of the particle at the origin in cosinusoidal form is shown in the figure.
Try to find (1) the vibration function of the particle at the origin, (2) the wave function of the planar simple harmonic wave according to the origin.
Answer:
n the case of linear motion, the change occurs in the magnitude of the velocity, the direction remaining constant.
In the case of circular motion, the magnitude of the velocity remains constant, the change in its direction occurring.
Explanation:
Velocity is a vector therefore it has magnitude and direction, a change in either of the two is the consequence of an acceleration on the system.
In the case of linear motion, the change occurs in the magnitude of the velocity, the direction remaining constant.
= (v₂-v₁)/Δt
In the case of circular motion, the magnitude of the velocity remains constant, the change in its direction occurring.
= v2/R
In the general case, both the module and the address change
a = Ra ( a_{t}^2 + a_{c}^2)