Answer:

Explanation:
The time lag between the arrival of transverse waves and the arrival of the longitudinal waves is defined as:

Here d is the distance at which the earthquake take place and
is the velocity of the transverse waves and longitudinal waves respectively. Solving for d:

Average speed = (total distance covered) / (time to cover the distance)
-- Traveling at 40 mph for 1 hour, the distance covered is 40 miles.
-- Traveling at 60 mph for 1 hour, the distance covered is 60 miles.
-- Total distance covered = (40 miles) + (60 miles) = 100 miles
-- Total time = (1 hour) + (1 hour) = 2 hours
-- Average speed = (100 miles) / (2 hours)
<em>Average speed = 50 miles per hour</em>
Answer:
D. Flow separation is caused due to adverse pressure gradient in the flowing fluid.
Explanation:
Flow separation :
When adverse pressure gradient become dominate then phenomenon of flow separation occurs.In the other words when boundary layer is form against the adverse pressure then phenomenon of flow separation occurs.The adverse pressure means a opposing which act in the opposite to the direction of fluid flow.Due to flow separation eddy formation occurs and these eddy leads to increases the losses in the fluid flow.Due to flow separation fluid leaves the solid surface and form eddies.
So the answer is D.
Answer:
v_avg = 37 km/h
Explanation:
To find the average velocity in the complete trajectory you use the following formula:
( 1 )
v1: velocity in the first part of the trajectory = 70 km/h
v2: velocity in the second part of the trajectory = ?
You calculate v2 by using the following equation for a motion with constant velocity:

you replace the values of v1 and v2 in (1) and you obtain:

hence, the average velocity is 37 km/h