Answer:
The driver's average velocity is 82.35 km/h.
Explanation:
Given:
The motion of the driver can be divided into 3 parts:
i. Displacement of the driver in 1.5 hours = 135 km
ii. Rest for 45 minutes.
iii. Displacement in next 2 hours = 215 km
The direction of motion remains same (east).
Now, total displacement of the driver is, 
km.
Rest time is 45 minutes. Converting it to hours, we need to use the conversion factor 
hour.
So, 45 minutes in hours is equal to 
hours.
Now, total time taken for the complete journey is, 
Average velocity is given as:
Therefore, the driver's average velocity is 82.35 km/h
Answer:
Explanation:
We have,
Mass of Mars is, 
Mass of its moon Phobos, 
Distance between Mars and Phobos, d = 9378 km
It is required to find the gravitational force between Mars and Phobos. The force between two masses is given by
Plugging all values, we get :
So, the gravitational force is 
.
Because the sun evaporates the water out of the clothes
Albert Einstein came up with the theory of general relativity to explain the law of gravity, whilst Newton's three laws of gravity is universal. To understand this further, it's best to understand it in scientific terms.
The weird thing about science is that words that are used in a colloquial sense may have a completely opposite definition in scientific terms.
A law in science is a constant and invariable statement that is universal. Wherever you may be in the universe, Newton's three laws of gravity will always be applied.
The word "theory" doesn't imply conjecture or an idea someone made up after a night of drinking. In science, a theory is the highest level of certainty behind mathematical proof -- which isn't even a part of science, obviously. A theory has to be substantiated by all available evidence and contradicted by none. All theories also have to have to be falsifiable. For this reason, theories can never be proven. Einstein's theory of general relativity has great predictive power, but in some cases, the predictions aren't always constant. Theories are often revised to fit new available evidence.
