Answer:
The frequency heard y the ship is 70 MHz.
Explanation:
True frequency, f = 50 MHz
speed of source, vs = 0
speed of observer, vo = 0.4 c
Let the frequency heard by the ship is f'.
Use the formula of doppler's effect
Answer:
(a) t = 1.67 s
(b) s₂ = 45 m
Explanation:
Here, we use the formula:
s = vt
FOR Seth:
s₁ = v₁t₁
where,
s₁ = distance covered by Seth
v₁ = speed of Seth = 9 m/s
t₁ = time taken by Seth
FOR Mack:
s₂ = v₂t₂
where,
s₂ = distance covered by Mack
v₂ = speed of Mack = 27 m/s
t₂ = time taken by Mack
since, initially Mack is 30 m behind Seth. Therefore,
(a)
s₂ = s₁ + 30 m
using formulae:
v₂t₂ = v₁t₁ + 30 m
but, the time of catching is same for both (t₁ = t₂ = t)
v₂t = v₁t + 30 m
using values:
(27 m/s)t - (9 m/s)t = 30 m
t = (30 m)/(18 m/s)
<u>t = 1.67 s</u>
(b)
s₂ = v₂t
using values:
s₂ = (27 m/s)(1.67 s)
<u>s₂ = 45 m</u>
It would be D) Electromagnetic waves
Hope it helped!
Answer:
Indirect
Explanation:
because jffhfdbkfdblfdnlf
Force equals mass*acceleration
F = ma
Given m = 54.87 kg, a = 9.8 m/s^2
F = (54.87)(9.8)
F = 537.726
F = 538 N
A force of al least 538 Newtons is required to move the object.
