1) 3 miles/Hour
The speed is defined as the distance covered divided by the time taken:
where
d = 1.5 mi is the distance
t = 0.5 h is the time taken
Substituting,
2) 1.34 m/s south
Velocity, instead, is a vector, so it has both a magnitude and a direction. We have:
is the displacement in meters
is the time taken in seconds
Substituting,
And the direction of the velocity is the same as the displacement, so it is south.
Answer:
The number of people at game are approximately 22909
Explanation:
Given data
When one person shout
When n number of person shout together
The sound intensity level during one person shout is given by:
The sound intensity level during n number of person shout is given by:
Since each person generates same sound intensity and hence total number of persons can be determined as
Hence
The number of people at game are approximately 22909
Answer:
The rate of change of distance between the two ships is 18.63 km/h
Explanation:
Given;
distance between the two ships, d = 140 km
speed of ship A = 30 km/h
speed of ship B = 25 km/h
between noon (12 pm) to 4 pm = 4 hours
The displacement of ship A at 4pm = 140 km - (30 km/h x 4h) =
140 km - 120 km = 20 km
(the subtraction is because A is moving away from the initial position and the distance between the two ships is decreasing)
The displacement of ship B at 4pm = 25 km/h x 4h = 100 km
Using Pythagoras theorem, the resultant displacement of the two ships at 4pm is calculated as;
r² = a² + b²
r² = 20² + 100²
r = √10,400
r = 101.98 km
The rate of change of this distance is calculated as;
r² = a² + b²
r = 101.98 km, a = 20 km, b = 100 km