In physic, velocity is a vector quantity. You specify a velocity if you know its magnitude and its direction
On the other hand, speed is a scalar quantity. Speed has magnitude but no direction.
The correct answer for the question that is being presented above is this one: "D. smaller than." In a practical machine, the power output is smaller than the power input. The power output is smaller than the power input as most of the energy usually has been converted to heat in the process.
Answer: 
At sea level, there is one standard atmospheric pressure which is equal to 101.325 kilopascals.
The pressure of faintest sound that a human ear can hear is 20 micro-pascals.
taking the ratio of two:


Hence, the atmospheric pressure at sea level is
times greater than the faintest sound that a human ear can hear.
Answer:
d = 175 miles
Explanation:
Train is moving towards East with constant speed of 50 mph
While car is moving at speed of 30 mph
so after t = 3 hours
the distance moved by the train is given as


at the same time the distance moved by the car is given as

now we know that both car and train is moving perpendicular to each other
So the distance between them after t = 3 hours is given as


