Which of the following numbers is between 0.40 and 0.47?

Mathematics

1 answer:

ira [324]3 years ago

3 0

Answer:

C. 21/50 because 21/50 written in a decimal is 0.42

You might be interested in

I really need the answers for these I don't understand this

Yuri [45]

I tryed my best to figure out what all of the numbers were. if i got any wrong then please tell me and i will put the right answer in the comments.

1) 3/5= 5/x (cross multiply)
3x=5(5)
3x=25
x= 25/3 -or- 8.33

2) 2/4=x/12 (cross multiply)
 2(12)=4x
 24=4x
 6=x
3) 10/x=5/9 (cross multiply)
10(9)=5x
90=5x
18=x
4) 5/5=x/18 (cross multiply)
5(18)=18x
90=18x
5=x

8 0

3 years ago

A spring with a spring constant k of 100 pounds per foot is loaded with 1-pound weight and brought to equilibrium. It is then st

shutvik [7]

Answer:

Equation of movement y(t)

$y(t)=sin(10t-\pi/2)$

Amplitude: 1 inch

Period: 0.628 seconds

Step-by-step explanation:

If there is no friction, the amplitude will be the length it was streched from the equilibrium. In this case, this value is 1 inch

$A=1\,inch$

The period depends on the mass and the spring constant.

The formula for the period is:

$T=\frac{1}{f} =\frac{2/pi}{\omega} =2\pi\sqrt{\frac{m}{k}}=2\pi\sqrt{\frac{1}{100}}=2\pi*0.1=0.628\, s$

The model y(t) for the movement of the mass-spring system is

$y(t)=A\cdot sin(\omega t +\phi)\\\\A=1\\\\\omega=\sqrt{k/m} =\sqrt{100/1}=10\\\\y(0)=Asin(\phi)=-A\\\\ \phi=arcsin(-1)=-1.571=-\pi/2\\\\\\y(t)=sin(10t-\pi/2)$