5.38
21 divided by 3.9 is 5.38 and the equation for acceleration is change in velocity divided by time
Answer:
rise the air temperature is 0.179241 K
Explanation:
Given data
mass = 20000 kg
velocity = 18.5 m/s
long = 65 m
wide = 20 m
height = 12 m
density of the air = 1.20 kg/ m³
specific heat = 1020 J/(kg*K)
to find out
how much does the air temperature in the station rise
solution
we know here Energy lost by the train that is calculated by
loss in the kinetic energy that is = 1/2 m v²
loss in the kinetic energy = 0.5 × 20000 ×18.5²
loss in the kinetic energy is 3422500 J
and
this energy is used here to rise the air temperature that is KE / ( specific hat × mass )
so here
air volume = 65 ×20×12
air volume = 15600 m³
air mass = ρ × V = 1.2 × 15600
air mass = 18720 kg
so
rise the air temperature = 3422500 / ( 1020 × 18720)
rise the air temperature is 0.179241 K
Answer:
A
A fox and hawk can be both a predator and prey
Answer;
A)S(t)=96t-16t² +432
B)it will take 9 seconds for the ball to reach the ground.
C)864feet
Explanation:
We were given an initial height of 432 feet.
And v(t)= 96-32t
A) we are to Find s(t), the function giving the height of the ball at time t
The position, or heigth, is the integrative of the velocity. So
S(t)= ∫(96-32)dt
S(t)=96t-16t² +K
S(t)=96t-16t² +432
In which the constant of integration K is the initial height, so K= 432
b) we need to know how long will the ball take to reach the ground
This is t when S(t)= 0
S(t)=96t-16t² +432
-16t² +96t +432=0
This is quadratic equation, if you solve using factorization method we have
t= -3 or t= 9
Therefore, , t is the instant of time and it must be a positive value.
So it will take 9 seconds for the ball to reach the ground.
C)V=s/t
Velocity= distance/ time
=96=s/9sec
S=96×9
=864feet
Answer:
= 2 beats per seconds
Explanation:
- From |f -f'| = modulus of the difference between the frequency given.
- Difference between the frequency will give us the number of beat per seconds.
These also shows how to get the period of the tuning forks.
