Increasing the mass attached to a spring will increase it's vibrational period - this is true. Imagine placing an elephant at the end of a bungee cord vs an apple, the apple will recoil faster than the elephant.
-cant travel through space since there's no molecules to travel through
-sound travels 4.3 times faster in water than air
-sounds are waves that pass through our ears via vibrations and travel by vibrations of molecules
-different types of sound like audible, inaudible, infrasonic, ultrasonic,
-sounds waves are either longitudinal, mechanical and pressure waves
-sound travels at 767 miles per hour
Answer:
net force
Explanation:
net force is the total amount of force exerted on an object.
First the velocity drops to zero in 1.2 secs. In those seconds it went upwards for 7.2 m, then it went from 87.2 to 0m. x-x0=v0*t+1/2*g*t^2 ergo t=sqrt(2x/g) that is 4.1761 s. Finally the total time required is 5.3761 s
Answer:
The speed decreases.
Explanation:
This can be explained using the conservation of linear momentum.
Since there is no friction, the initial moment of the train must be equal to its linear moment after it is filled with water.
the initial linear momentum is

where
is the initial mass of the train, and
the initial speed of the train.
And linear momentum after the water filled the train car is

where
is mass of the train after the rain, and
the speed of the train after the rain
<u>the equality must be fulfilled:</u>

We know that if water is added to the train,
that is the mass after the water is added, is greater than
which is the mass of the train without the water.
Therefore, in order for the conservation of the linear momentum to be fulfilled: 
the speed after the water is added (
) must be smaller than the initial train speed (
) . So the speed of the car decreases.