We have the equation of motion 
, where s is the displacement, a is the acceleration, u is the initial velocity and t is the time taken.
Here displacement = 135 m, Initial velocity = 0 m/s, acceleration = 9.81 
Substituting
A box falls out of a stationary helicopter hovering 135 m above the ground will take 5.25 seconds to reach the ground.
Answer:
D. Half as great
Explanation:
Since we know that the friction force between the surface of crate and ground is given as
so here we know that
= friction coefficient between two surfaces which depends on the effective contact area between two surfaces
= normal force due to the object
So when we turn the object on another side such that the surface area is half then the friction coefficient will become also half
So here the friction force will also reduce to half
so correct answer will be
D. Half as great
Absolute, Atmospheric, Differential, and Gauge Pressure
Answer:
F = 852 N
Explanation:
We apply Newton's second law to the trailer :
F = m*a Formula (1)
F : net force exerted by the truck on the trailer Newtons (N)
m : mass of the trailer in kilograms (kg)
a : acceleration of the trailer in meters over second square (m/s²)
Data
a=1.20 m/s² : acceleration of the trailer
m=710 kg : mass of the trailer
We replace data in the Formula (1) to calculate the net force exerted by the truck on the trailer
F = (710 kg)*(1.20 m/s²)
F = 852 N
Yes, of course, a good example would be us.
