Some car driving 60 mph on the highway uses 8 L of fuel per hour. The heating value HV of the fuel is about 42.4 MJ/kg and the density is 750 kg/m3 . If the thermal efficiency of the engine is 25%, then what is the power available at the crankshaft axis in bhp

The value is  

Explanation:

From the question we are told that

   The velocity of the car is

    Th amount of fuel used in an hour is

    The heating value of the fuel is

    The thermal efficiency of the engine is

Generally the rate at which the fuel is consumed is mathematically represented as

Here is the density of fuel  with value  

=>        

Generally the power available at the crankshaft axis is mathematically represented as

=>        

=>        

Converting to  horse power

=>

Generally the power available in the crankshaft in break hoarse power is mathematically evaluated as

=>      

=>      

=>  

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1.            c. is smaller

2.            d) concrete operational

3.            b) interaction with the environment – the children interact with their environment can them learn more.

4.            a) parents who reason openly with children can limit a child’s cognitive ability.