The average speed of the car for the entire trip can be calculate by using:
where S is the total distance covered by the car, and t is the total time taken.
The total distance travelled by the car is:
while the total time taken is:
so, the average speed of the car is:
so, the correct answer is (3) 85 km/h.
Explanation:
It is given that,
Total weight of the piston, W = F = 70 N
Area of the piston,
Let P is the pressure exerted on the piston by the gas. The force per unit area is called the pressure exerted pressure of the gas. Mathematically, it is given by :
We know that the atmospheric pressure is given by :
So, the pressure is given by :
Hence, this is the required solution.