Answer:
t = 6.68 seconds
Explanation:
The acceleration of the automobile, 
Initial speed of the automobile, u = 91 km/hr = 25.27 m/s
Final speed of the automobile, v = 104 km/hr = 28.88 m/s
Let t is the time taken to accelerate from u to v. It can be calculated as the following formula as :
t = 6.68 seconds
So, the time taken by the automobile to accelerate from u to v is 6.68 seconds. Hence, this is the required solution.
Since the stone is travelling, the displacement cannot be constant. This leaves the last 2 choices as possibilities. Now consider the acceleration that can act on the stone. Acceleration due to gravity is the only one. That means the horizontal component of the stone has to be constant since there is no acceleration in the horizontal direction.
Answer:
Since the waves must carry a great deal of visual as well as audio information, each channel requires a larger range of frequencies than simple radio transmission. TV channels utilize frequencies in the range of 54 to 88 MHz and 174 to 222 MHz. (The entire FM radio band lies between channels 88 MHz and 174 MHz.)
It must have a medium. It must travel in empty space. Mechanical waves are waves which needs medium of propogation.
