Explanation:
First, we need to determine the distance traveled by the car in the first 30 minutes, .
Notice that the unit measurement for speed, in this case, is km/hr. Thus, a unit conversion of from minutes into hours is required before proceeding with the calculation, as shown below
Now, it is known that the car traveled 40 km for the first 30 minutes. Hence, the remaining distance, , in which the driver reduces the speed to 40km/hr is
.
Subsequently, we would also like to know the time taken for the car to reach its destination, denoted by .
.
Finally, with all the required values at hand, the average speed of the car for the entire trip is calculated as the ratio of the change in distance over the change in time.
Therefore, the average speed of the car is 50 km/hr.
Answer: As per the question, a ray of light is incident on a surface and it is partly reflected and refracted. The incident light is an unpolarised light. The reflected light is partially polarised.
If the angle of incidence becomes equal to the Brester angle (polarising angle), then the reflected light is completely plane polarised.
Answer:
Explanation:
<u>Dimensional Analysis</u>
It's given the relation between quantities A, B, and C as follows:
and the dimensions of each variable is:
Substituting the dimensions into the relation (the coefficient is not important in dimension analysis):
Operating:
Equating the exponents:
Adding both equations:
Solving:
Answer:
Start with what the paragraph is about and put it basically in your own words