Answer:
f' = 3665.51 Hz
Explanation:
given,
speed of the hawk = 24.7 m/s
frequency of screech emitted by the hawk = 3400 Hz
speed of sound = 331 m/s
By Doppler's effect

f' is the frequency received by the mouse
v is the speed of the sound
v_s is the speed of the hawk
now,

f' = 1.078 x 3400
f' = 3665.51 Hz
The frequency received by the stationary mouse is equal to 3665.51 Hz
Answer:
C
Explanation:
Rocks with hotter temperatures sank to the bottom of the Earth. The rocks with the hottest temperature became the core and the rocks with the least amount of heat became the crust.
Hope this helps!
Answer:
net force
Explanation:
Net force felt by an object.
Answer:

Explanation:
given,
refractive index of lens, n = 1.70
Radius of curvature of front surface. R₁ = 20 cm
Radius of curvature of the back surface, R₂ = 30 cm
focal length= ?

R₁ = +20 cm
R₂ = -30 cm
n = 1.70




the focal length of the lens is equal to 17.15 cm
Answer:
The rock will reach 9 m from the ground at eaxactly 5.06 s after it was initially thrown upwards.
Explanation:
We will use the equations of motion for this.
u = initial velocity of the rock = 22 m/s
g = acceleration due to gravity = -9.8 m/s²
y = vertical position of the rock at a time t = 9 m
y₀ = initial height of the rock = 25 m
t = time it takes for the rock to reach height of 9 m.
(y-y₀) = ut + 0.5gt²
(9 - 25) = 22t + 0.5(-9.8)t²
- 14 = 22t - 4.9t²
4.9t² - 22t - 14 = 0
solving this quadratic equation,
t = 5.055 s or - 0.565 s
Since time cannot be negative,
t = 5.055 s = 5.06 s
Hope this Helps!!!