Answer:
Factor by which kinetic energy increase = 4 times
Step-by-step explanation:
Given,
- Mass of the car, v1 = 1500 kg
- initial speed of car = 35 miles/h
![=\dfrac{35\times 1609.34}{3600}\ m/s](https://tex.z-dn.net/?f=%3D%5Cdfrac%7B35%5Ctimes%201609.34%7D%7B3600%7D%5C%20m%2Fs)
= 15.64 m/s
Initial kinetic energy of the car is given by,
![k_1\ =\ \dfrac{1}{2}.m.v_1^2](https://tex.z-dn.net/?f=k_1%5C%20%3D%5C%20%5Cdfrac%7B1%7D%7B2%7D.m.v_1%5E2)
![=\ \dfrac{1}{2}\times 1500\times (15.64)^2\ joule](https://tex.z-dn.net/?f=%3D%5C%20%5Cdfrac%7B1%7D%7B2%7D%5Ctimes%201500%5Ctimes%20%2815.64%29%5E2%5C%20joule)
= 183606.46 J
- Final velocity of car v2 = 70 miles/hour
![=\dfrac{70\times 1609.34}{3600}](https://tex.z-dn.net/?f=%3D%5Cdfrac%7B70%5Ctimes%201609.34%7D%7B3600%7D)
= 31.29 m/s
So, final kinetic energy of car is given by
![k_2\ =\ \dfrac{1}{2}.m.v_2^2](https://tex.z-dn.net/?f=k_2%5C%20%3D%5C%20%5Cdfrac%7B1%7D%7B2%7D.m.v_2%5E2)
![=\ \dfrac{1}{2}\times 1500\times (31.29)^2](https://tex.z-dn.net/?f=%3D%5C%20%5Cdfrac%7B1%7D%7B2%7D%5Ctimes%201500%5Ctimes%20%2831.29%29%5E2)
= 734425.84 J
Now, the ratio of final to initial kinetic energy can be given by,
![\dfrac{k_2}{k_1}=\ \dfrac{734425.84}{183606.46}](https://tex.z-dn.net/?f=%5Cdfrac%7Bk_2%7D%7Bk_1%7D%3D%5C%20%5Cdfrac%7B734425.84%7D%7B183606.46%7D)
Hence, the kinetic energy will increase by 4 times.
Answer:
A. Positive
Step-by-step explanation:
They ask us about the relationship between reading and grades.
First you have to go to the first part of the statement that says:
"Dr. Yancy conducted a correlation study in which she found that the more time children in her study read at home the better they performed in school"
In this case they tell us that there is a positive correlation, that the more you read the better your performance in school is.
Performance is your grades, and home study can be reading, so the score is positive in the second half, too.
Answer: Quotient means when you divided a number by another number.
Our first number will be 48 and also in this problem lets have that second "number" be x.
So 48/x is the quotient.
Answer:
$18
Step-by-step explanation:
Given:
y = 0.9x - 4.5
Where,
x = age in years
y = hourly pay in dollars
what is the best prediction for the hourly pay of a 25 year old?
That is, find y when x=25
y = 0.9x - 4.5
= 0.9(25) - 4.5
= 22.5 - 4.5
= 18
y = $18
The prediction for the hourly pay of a 25 year old is $18
U divide 24 to 9, which is not going to be an exact number, but you can do 9times2=18 so then if you do it in a long division bar you will put 2 on top then minus 18 from 24 which will give you 6, then ur answer is going to be 2 6/9 the nine stays the same (the denominator stay put)
HOPE IT HELPS :)