Answer: atmospheric is air by the earth and pressure is just someone or something doing it
Explanation:
Explanation:
When a man falls on a hard cemented floor his momentum reduced to zero in a very short time and hurt the man. Whereas when a man falls on a heap of sand. As sand can compress, it takes longer time for the man to hit the ground (or hard surface)
Lets assume that s is the speed of the slower train and f is the speed of the faster train.
s = f - 16
f = 150 / t
s = 170 / ( t+2 )
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170 / ( t+2 ) = 150 / t - 16 / t * ( t + 2 )
170 t = 150 * ( t + 2 ) - 16 t * ( t + 2 )
170 t = 150 t + 300 - 16 t² - 32 t
16 f² + 52 t - 300 = 0 / : 4 ( We will divide both sides of the equation by 4 )
4 t² + 13 t - 75 = 0
t 1/2 = ( -13 + √(169 + 1200 ) )/ 8
t = ( - 13 + 37 ) / 8 = 24 / 8 = 3
t = 3 h
s = 170 : ( 3 + 2 ) = 170 : 5 = 34 mph
Answer: The speed of the slower train is 34 mph.
Answer:
So time taken by block to travel 0.5 m from rest will be 0.4853 sec
Explanation:
We have given mass of the block m = 6.7 kg
angle of inclination 
Distance traveled s = 0.5 m
Initial velocity u = 0 m/sec
Acceleration of the block 
From second equation of motion we know that 
So 

t = 0.4853 sec
So time taken by block to travel 0.5 m from rest will be 0.4853 sec
Answer:
The terminal speed of his is 137.68 m/s.
Explanation:
Given that,
Mass of skydiver = 78 kg
Area of box
Drag coefficient = 0.80
Density of air 
We need to calculate the terminal velocity
Using formula of drag force

Where,
= density of air
A = area
C= coefficient of drag
Put the value into the formula




Hence, The terminal speed of his is 137.68 m/s.