Speed = Distance/ Time
Speed = 400 / 4
Speed = 100 km/hr.
100 km per hour.
Shrek is love shrek is life stan shrek
Answer:
After 12 seconds, the area enclosed by the ripple will be increasing rapidly at the rate of 1206.528 ft²/sec
Explanation:
Area of a circle = πr²
where;
r is the circle radius
Differentiate the area with respect to time.

dr/dt = 4 ft/sec
after 12 seconds, the radius becomes = 
To obtain how rapidly is the area enclosed by the ripple increasing after 12 seconds, we calculate dA/dt


dA/dt = 1206.528 ft²/sec
Therefore, after 12 seconds, the area enclosed by the ripple will be increasing rapidly at the rate of 1206.528 ft²/sec
Answer:
A) - 1.8 m/s
Explanation:
As we know that whole system is initially at rest and there is no external force on this system
So total momentum of the system must be conserved
so we will have

now plug in all data into above equation



so correct answer is
A) - 1.8 m/s
Answer:
Option A.
A fan is turned from high speed to low speed.
Explanation:
It is important to note that air is also a fluid.
In a system, static pressure of air increases with the speed of rotation of the fan. This is because when the speed of the fan is increased, the force with which it is pushing the air molecules is increased. Since pressure is a relationship between force and area, the pressure of the air molecules will be increased.
Conversely, when the speed of the fan is reduced, the priming force on the air molecules will be reduced, hence the pressure of the air will drop.
This makes option A the correct option