Answer:
4.02 km/hr
Explanation:
5 km/hr = 1.39 m/s
The swimmer's speed relative to the ground must have the same direction as line AC.
The vertical component of the velocity is:
uᵧ = us cos 45
uᵧ = √2/2 us
The horizontal component of the velocity is:
uₓ = 1.39 − us sin 45
uₓ = 1.39 − √2/2 us
Writing a proportion:
uₓ / uᵧ = 121 / 159
(1.39 − √2/2 us) / (√2/2 us) = 121 / 159
Cross multiply and solve:
159 (1.39 − √2/2 us) = 121 (√2/2 us)
220.8 − 79.5√2 us = 60.5√2 us
220.8 = 140√2 us
us = 1.115
The swimmer's speed is 1.115 m/s, or 4.02 km/hr.
Answer:
A) 0.660 g/ml
B) 1.297 ml
C) 0.272 g
Explanation:
Every substance, body or material has mass and volume, however the mass of different substances occupy different volumes. This is where density
appears as a physical characteristic property of matter that establishes a relationship between the mass
of a body or substance and the volume
it occupies:
(1)
Knowing this, let's begin with the answers:
<h2 /><h2>Answer A:</h2>
Here the mass is
and th volume
Solving (1) with these values:
(2)
(3)
<h2>Answer B:</h2>
In this case the mass of a sample is
and its density is
.
Isolating
from (1):
(4)
(5)
(5)
<h2>Answer C:</h2>
In this case the volume of a sample is
and its density is
.
Isolating
from (1):
(6)
(7)
(8)
This phenomena is also called the Doppler shift. When the source of light is approaching towards an observer, the color tends to be blue shifted, but when the source is moving away or being stretch, the color tends to red shifted. In astronomy it can be use how fast galaxy is moving towards us or how fast it moves away.
Answer:
v = 20.31 m/s
Explanation:
p = mv -> v = p/m = 32,500 kg*m/s / 1,600 kg = 20.31 m/s