Answer:
Option B
Explanation:
Speed of a wave is denoted by:
v=fλ
where f is the frequency which is unchanged 15Hz and λ is the new wavelength which is 28m
v=fλ

Answer:
Explanation:
a ) The earth rotates by 2π radian in 24 x 60 x 60 s
so angular speed ( w ) = 2π / (24 x 60 x 60) = 7.268 x 10⁻⁵ rad / s
b ) Linear speed of city of Arlington ( v ) = w r = w R Cosλ where R is radius of the earth and λ is latitude .
v = 7.268 x 10⁻⁵ x 6.371 x 10⁶ cos 32.7357
389.5 m /s
acceleration = w² r = w² R Cos 32.7357
= (7.268 x 10⁻⁵ )² x 6.371 x 10⁶ x cos 32.7357
=283.08 x 10⁻⁴ m/s²
c) velocity ratio =
w r /w R =
R cos 32.73/ R
= Cos 32.73
= 0.84 .
Answer:
23.52 m/s
Explanation:
The following data were obtained from the question:
Time taken (t) to reach the maximum height = 2.4 s
Acceleration due to gravity (g) = 9.8 m/s²
Initial velocity (u) =..?
At the maximum height, the final velocity (v) is zero. Thus, we can obtain how fast the rock (i.e initial velocity)
was thrown as follow:
v = u – gt (since the rock is going against gravity)
0 = u – (9.8 × 2.4)
0 = u – 23.52
Collect like terms
0 + 23.52 = u
u = 23.52 m/s
Therefore, the rock was thrown at a velocity of 23.52 m/s.
Answer:
39.6 m/s
Explanation:
Taking down to be positive:
Given:
v₀ = 0 m/s
a = 9.8 m/s²
Δy = 80 m
Find: v
v² = v₀² + 2aΔy
v² = (0 m/s)² + 2 (9.8 m/s²) (80 m)
v = 39.6 m/s