Explanation:
The machine whose efficiency is 100% is known as perfect machine .This machine is not possible in real life because every machine is affected by the overcoming friction due to which is efficiency become less than hundred percent .
 
        
             
        
        
        
Answer: The molar heat capacity of aluminum is 
Explanation:
 
As we know that,  
 
![m_1\times c_1\times (T_{final}-T_1)=-[m_2\times c_2\times (T_{final}-T_2)]](https://tex.z-dn.net/?f=m_1%5Ctimes%20c_1%5Ctimes%20%28T_%7Bfinal%7D-T_1%29%3D-%5Bm_2%5Ctimes%20c_2%5Ctimes%20%28T_%7Bfinal%7D-T_2%29%5D) .................(1)
         .................(1)
where,
q = heat absorbed or released
 = mass of water = 130.0 g
 = mass of water = 130.0 g
 = mass of aluminiunm = 23.5 g
 = mass of aluminiunm = 23.5 g
 = final temperature
=
 = final temperature
=  
 = temperature of water =
 = temperature of water =  
 = temperature of aluminium =
 = temperature of aluminium =  
 = specific heat of water=
 = specific heat of water= 
 = specific heat of aluminium= ?
 = specific heat of aluminium= ?
Now put all the given values in equation (1), we get
![130.0\times 4.184\times (299-296)=-[23.5\times c_2\times (299-373)]](https://tex.z-dn.net/?f=130.0%5Ctimes%204.184%5Ctimes%20%28299-296%29%3D-%5B23.5%5Ctimes%20c_2%5Ctimes%20%28299-373%29%5D) 
 
Molar mass of Aluminium = 27 g/mol
Thus molar heat capacity =
 
        
             
        
        
        
The direction of its displacement wil be 
c.northeast 
In fact, the dog walks north for 10 meters and east for another 10 meters. The path of the dog can be represented with two vectors, A pointing north (of magnitude 10 meters) and B pointing east (of magnitude 10 meters). The direction of the resultant vector (due to east) will be given by


and the direction will be north-east.
 
        
             
        
        
        
Answer: 110000
Explanation:
26/9=30.5555555556
30.5555555556 x 60=1833.33333333
110000 x 60=110000