Answer:
![H_0: \beta_2 = 3\beta_1](https://tex.z-dn.net/?f=H_0%3A%20%5Cbeta_2%20%3D%203%5Cbeta_1)
Explanation:
The null hypothesis is the hypothesis that there is no significant difference between specified populations and that any observed difference is due to sampling/experimental error.
We would like to test that one year of attending a university with regression parameter
is worth 3 years of attending a junior college with regression parameter
in terms of the wages earned.
In the model:![log(wage)=\beta_0+\beta_1jc+\beta_2univ+\beta_3exper + u](https://tex.z-dn.net/?f=log%28wage%29%3D%5Cbeta_0%2B%5Cbeta_1jc%2B%5Cbeta_2univ%2B%5Cbeta_3exper%20%2B%20u)
The null hypothesis will therefore be:
![H_0: \beta_2 = 3\beta_1](https://tex.z-dn.net/?f=H_0%3A%20%5Cbeta_2%20%3D%203%5Cbeta_1)
1.radio waves
2.microwaves
3.infrered
Answer:
The work done by friction was ![-4.5\times10^{5}\ J](https://tex.z-dn.net/?f=-4.5%5Ctimes10%5E%7B5%7D%5C%20J)
Explanation:
Given that,
Mass of car = 1000 kg
Initial speed of car =108 km/h =30 m/s
When the car is stop by brakes.
Then, final speed of car will be zero.
We need to calculate the work done by friction
Using formula of work done
![W=\Delta KE](https://tex.z-dn.net/?f=W%3D%5CDelta%20KE)
![W=K.E_{f}-K.E_{i}](https://tex.z-dn.net/?f=W%3DK.E_%7Bf%7D-K.E_%7Bi%7D)
![W=\dfrac{1}{2}mv_{f}^2-\dfrac{1}{2}mv_{f}^2](https://tex.z-dn.net/?f=W%3D%5Cdfrac%7B1%7D%7B2%7Dmv_%7Bf%7D%5E2-%5Cdfrac%7B1%7D%7B2%7Dmv_%7Bf%7D%5E2)
Put the value of m and v
![W=0-\dfrac{1}{2}\times1000\times(30)^2](https://tex.z-dn.net/?f=W%3D0-%5Cdfrac%7B1%7D%7B2%7D%5Ctimes1000%5Ctimes%2830%29%5E2)
![W=-450000 \ J](https://tex.z-dn.net/?f=W%3D-450000%0A%5C%20J)
![W=-4.5\times10^{5}\ J](https://tex.z-dn.net/?f=W%3D-4.5%5Ctimes10%5E%7B5%7D%5C%20J)
Hence, The work done by friction was ![-4.5\times10^{5}\ J](https://tex.z-dn.net/?f=-4.5%5Ctimes10%5E%7B5%7D%5C%20J)
Answer:
1421 seconds or 23.67 minutes
Explanation:
Q = Heat = 1200 W
c = Specific heat of human body = 3480 J/kgK
= Change in temperature = (44-37)°C
t = Time taken
![Q=\dfrac{mc\Delta T}{t}\\\Rightarrow t=\dfrac{mc\Delta T}{Q}\\\Rightarrow t=\dfrac{70\times 3480\times (44-37)}{1200}\\\Rightarrow t=1421\ s](https://tex.z-dn.net/?f=Q%3D%5Cdfrac%7Bmc%5CDelta%20T%7D%7Bt%7D%5C%5C%5CRightarrow%20t%3D%5Cdfrac%7Bmc%5CDelta%20T%7D%7BQ%7D%5C%5C%5CRightarrow%20t%3D%5Cdfrac%7B70%5Ctimes%203480%5Ctimes%20%2844-37%29%7D%7B1200%7D%5C%5C%5CRightarrow%20t%3D1421%5C%20s)
The time student jogs before irreversible body damage occurs is 1421 seconds or 23.67 minutes
Answer:
A natural magnet is a magnet that occurs naturally in nature. Artificial magnets are magnets made by people. ... An example of a natural magnet is the lodestone, also called magnetite. Other examples are pyrrhotite, ferrite, and columbite.