Answer:
993.52 Hz
Explanation:
The frequency of sound emitted by the stationery train is 1057 Hz.
The car travels away from the train at 20.6 m/s.
The frequency the observer hears is given by the formula:

where v = velocity of sound = 343 m/s
vo = velocity of observer
f = frequency from source
This phenomenon is known as Doppler's effect.
Therefore:

The frequency heard by the observer is 993.52 Hz.
Answer:
The object has 1250 Joules of Kinetic Energy.
Explanation:
Kinetic Energy =
mass*velocity²
KE =
mv²
KE =
(100kg)(5m/s)²
KE =
(100kg)(25m/s²)
KE = 1250
KE = 1250J
Answer:
Bernoulli's equation states mathematically that if a fluid is flowing through a tube and the tube diameter decreases, then the velocity of the fluid increases, the pressure decreases, and the mass flow (and therefore volumetric flow) remains constant so long as the air density is constan
Explanation:
i would choose a for 945 and a for faster
Answer:
vector quantities are resolved into their component form (along the x and y-axis) before adding them. Let us assume that two vectors are
→
a
=
x
1
^
i
+
y
1
^
j
and
→
b
=
x
2
^
i
+
y
2
^
j
, we can find the sum of two vectors as follows.
→
a
+
→
b
=
x
1
^
i
+
y
1
^
j
+
x
2
^
i
+
y
2
^
j
=
(
x
1
+
x
2
)
^
i
+
(
y
1
+
y
2
)
^
j
The direction of the sum of the vectors (with positive x-axis) is,
θ
=
tan
−
1
(
y
1
+
y
2
x
1
+
x
2
)